7/31/2019 7 Earth Materials
1/37
1 | P a g e
Chapter 7
Earth materials
Earth materials is a general term that includesminerals,rocks,soilandwater. These are the
naturally occurring materials found onEarththat constitute theraw materialsupon which our global
society exists. Earth materials are vital resources that provide the basic components for
life,agricultureandindustry.
Earth materials can also includemetalsandprecious rocks
Minerals close-up
A pile of mineralsThis image shows some of themost common minerals you'll findin rocks. This pilecontainsplagioclasefeldspar,potassiumfeldspar,quartz,muscovitemica,biotitemica,amphibole,olivine,andcalcite. Can you identify any
of them? Click on any mineral for aclose up view.
Quartz
Quartz is one of the most common mineralsin the Earth's crust. It is made up of silicondioxide (SiO2), otherwise known assilica.White sand is primarily made from quartz.Clickhereto find out more.
http://en.wikipedia.org/wiki/Mineralhttp://en.wikipedia.org/wiki/Mineralhttp://en.wikipedia.org/wiki/Mineralhttp://en.wikipedia.org/wiki/Rock_(geology)http://en.wikipedia.org/wiki/Rock_(geology)http://en.wikipedia.org/wiki/Rock_(geology)http://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Raw_materialhttp://en.wikipedia.org/wiki/Raw_materialhttp://en.wikipedia.org/wiki/Raw_materialhttp://en.wikipedia.org/wiki/Agriculturehttp://en.wikipedia.org/wiki/Agriculturehttp://en.wikipedia.org/wiki/Agriculturehttp://en.wikipedia.org/wiki/Industryhttp://en.wikipedia.org/wiki/Industryhttp://en.wikipedia.org/wiki/Industryhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Precious_stonehttp://en.wikipedia.org/wiki/Precious_stonehttp://en.wikipedia.org/wiki/Precious_stonehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#plagioclasehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#plagioclasehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#plagioclasehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#ksparhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#ksparhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#ksparhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#quartzhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#quartzhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#quartzhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#micahttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#micahttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#micahttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#micahttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#biotitehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#biotitehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#biotitehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#amphibolehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#amphibolehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#amphibolehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#olivinehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#olivinehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#olivinehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#calcitehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#calcitehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#calcitehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/coast/sand/sand.htmlhttp://geomaps.wr.usgs.gov/parks/coast/sand/sand.htmlhttp://geomaps.wr.usgs.gov/parks/coast/sand/sand.htmlhttp://geomaps.wr.usgs.gov/parks/coast/sand/sand.htmlhttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#calcitehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#olivinehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#amphibolehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#biotitehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#biotitehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#micahttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#micahttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#quartzhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#ksparhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#ksparhttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#plagioclasehttp://geomaps.wr.usgs.gov/parks/rxmin/mineral.html#plagioclasehttp://en.wikipedia.org/wiki/Precious_stonehttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Industryhttp://en.wikipedia.org/wiki/Agriculturehttp://en.wikipedia.org/wiki/Raw_materialhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Rock_(geology)http://en.wikipedia.org/wiki/Mineral7/31/2019 7 Earth Materials
2/37
2 | P a g e
Plagioclase feldspar
Plagioclase is a member ofthe feldspar mineral family. Plagioclasefeldspars are yet anothersilicatethat
contains considerable sodium or calcium.Feldspar crystals are stubby prisms, generallywhite to gray and a glassyluster. This varietyof plagioclase, called albite, is rich in sodium.
Potassium feldspar
Potassium feldspar is another member ofthe feldsparmineral family. Likeplagioclase feldspar, potassium feldsparsaresilicateminerals that contain aconsiderable amount of -you guessed it-potassium. Feldspar crystals are stubbyprisms, often pink to white. Somepotassium feldspars, such as the oneshown to the left have a streakyappearance (see closeup) called perthitic
texture.
Mica
Micas are another group ofsilicatemineralscomposed of varying amounts of potassium,magnesium, iron as well as aluminum, siliconand water.
Biotite
All micas form flat, book-like crystalsthat peal apart into individual sheetsoncleavageplanes. Crystals cleaveinto smooth flakes. Biotiteis dark,black or brown mica; muscovite,shown here, is light-colored or clearmica. Mica is so soft that you can
scratch it with a fingernail.
http://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossaryjkl.html#lusterhttp://geomaps.wr.usgs.gov/parks/misc/glossaryjkl.html#lusterhttp://geomaps.wr.usgs.gov/parks/misc/glossaryjkl.html#lusterhttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossaryc.html#cleavagehttp://geomaps.wr.usgs.gov/parks/misc/glossaryc.html#cleavagehttp://geomaps.wr.usgs.gov/parks/misc/glossaryc.html#cleavagehttp://geomaps.wr.usgs.gov/parks/misc/glossaryc.html#cleavagehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicahttp://geomaps.wr.usgs.gov/parks/misc/glossaryjkl.html#lusterhttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silica7/31/2019 7 Earth Materials
3/37
3 | P a g e
Amphibole
The amphiboles are a familyofsilicateminerals that form prism or needle-like crystals. Amphibole minerals generally
contain iron, magnesium, calcium andaluminum in varying amounts along with silicon,oxygen, and water. Hornblende, shown in thisimage, is a common dark green to black variety
of amphibole; it is a component in manyigneousandmetamorphicrocks.
Olivine
Olivine is anothersilicatemineralcontaining iron and magnesium. It is agreen, glassy mineral that forms at high
temperature. It is common inbasaltandinultramaficrocks. Gem-quality olivine iscalled peridote. A rock made up entirely ofolivine is called dunite.
Calcite
Calcite is made of calcium carbonate (CaCO3).Generally white to clear, it is easily scratchedwith knife. Most seashells are made of calcite orrelated minerals. This is the 'lime' oflimestone.
Physical properties of minerals
Classifying minerals can range from simple to very difficult. A mineral can be identified by several
physical properties, some of them being sufficient for full identification without equivocation. In other
cases, minerals can only be classified by more complexoptical, chemical orX-ray diffractionanalysis;
these methods, however, can be costly and time-consuming.
Physical properties commonly used are:[1]
Crystal structure and habit: See the above discussion of crystal structure. A mineral may show
good crystal habit or form, or it may be massive, granular or compact with only microscopically
visible crystals.
http://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossaryi.html#igneoushttp://geomaps.wr.usgs.gov/parks/misc/glossaryi.html#igneoushttp://geomaps.wr.usgs.gov/parks/misc/glossaryi.html#igneoushttp://geomaps.wr.usgs.gov/parks/misc/glossarymn.html#metamorphichttp://geomaps.wr.usgs.gov/parks/misc/glossarymn.html#metamorphichttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossaryb.html#basalthttp://geomaps.wr.usgs.gov/parks/misc/glossaryb.html#basalthttp://geomaps.wr.usgs.gov/parks/misc/glossaryb.html#basalthttp://geomaps.wr.usgs.gov/parks/misc/glossaryuv.html#ultramafichttp://geomaps.wr.usgs.gov/parks/misc/glossaryuv.html#ultramafichttp://geomaps.wr.usgs.gov/parks/misc/glossaryuv.html#ultramafichttp://geomaps.wr.usgs.gov/parks/misc/glossaryjkl.html#limestonehttp://geomaps.wr.usgs.gov/parks/misc/glossaryjkl.html#limestonehttp://geomaps.wr.usgs.gov/parks/misc/glossaryjkl.html#limestonehttp://en.wikipedia.org/wiki/Optical_mineralogyhttp://en.wikipedia.org/wiki/Optical_mineralogyhttp://en.wikipedia.org/wiki/Optical_mineralogyhttp://en.wikipedia.org/wiki/X-ray_diffractionhttp://en.wikipedia.org/wiki/X-ray_diffractionhttp://en.wikipedia.org/wiki/X-ray_diffractionhttp://en.wikipedia.org/wiki/Mineral#cite_note-Klein-0http://en.wikipedia.org/wiki/Mineral#cite_note-Klein-0http://en.wikipedia.org/wiki/Mineral#cite_note-Klein-0http://en.wikipedia.org/wiki/Mineral#cite_note-Klein-0http://en.wikipedia.org/wiki/X-ray_diffractionhttp://en.wikipedia.org/wiki/Optical_mineralogyhttp://geomaps.wr.usgs.gov/parks/misc/glossaryjkl.html#limestonehttp://geomaps.wr.usgs.gov/parks/misc/glossaryuv.html#ultramafichttp://geomaps.wr.usgs.gov/parks/misc/glossaryb.html#basalthttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicatehttp://geomaps.wr.usgs.gov/parks/misc/glossarymn.html#metamorphichttp://geomaps.wr.usgs.gov/parks/misc/glossaryi.html#igneoushttp://geomaps.wr.usgs.gov/parks/misc/glossarys.html#silicate7/31/2019 7 Earth Materials
4/37
4 | P a g e
Talc
Rough diamond.
Hardness: the physical hardness of a mineral is usually measured according to theMohs scale.
This scale is relative and goes from 1 to 10. Minerals with a given Mohs hardness can scratch the
surface of any mineral that has a lower hardness than itself.
Mohs hardness scale:[25]
1. TalcMg3Si4O10(OH)2
2. GypsumCaSO42H2O
3. CalciteCaCO3
4. FluoriteCaF2
5. ApatiteCa5(PO4)3(OH,Cl,F)
6. OrthoclaseKAlSi3O8
7. QuartzSiO2
8. TopazAl2SiO4(OH,F)2
9. CorundumAl2O3
10.DiamondC (pure carbon)
Lusterindicates the way a mineral's surface interacts with light and can range from dull to glassy
(vitreous).
Metallic high reflectivity like metal:galenaandpyrite
Sub-metallic slightly less than metallic reflectivity:magnetite
Non-metallic lusters:
Adamantine brilliant, the luster ofdiamondalsocerussiteandanglesite
Vitreous the luster of a broken glass: quartz
Pearly iridescent and pearl-like: talc andapophyllite
Resinous the luster of resin:sphaleriteandsulfur
Silky a soft light shown by fibrous materials: gypsum andchrysotile
Dull/earthy shown by finely crystallized minerals: the kidney ore variety ofhematite
http://en.wikipedia.org/wiki/Hardness_(materials_science)http://en.wikipedia.org/wiki/Hardness_(materials_science)http://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardnesshttp://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardnesshttp://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardnesshttp://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardnesshttp://en.wikipedia.org/wiki/Mineral#cite_note-24http://en.wikipedia.org/wiki/Mineral#cite_note-24http://en.wikipedia.org/wiki/Mineral#cite_note-24http://en.wikipedia.org/wiki/Talchttp://en.wikipedia.org/wiki/Talchttp://en.wikipedia.org/wiki/Gypsumhttp://en.wikipedia.org/wiki/Gypsumhttp://en.wikipedia.org/wiki/Calcitehttp://en.wikipedia.org/wiki/Calcitehttp://en.wikipedia.org/wiki/Fluoritehttp://en.wikipedia.org/wiki/Fluoritehttp://en.wikipedia.org/wiki/Apatitehttp://en.wikipedia.org/wiki/Apatitehttp://en.wikipedia.org/wiki/Orthoclasehttp://en.wikipedia.org/wiki/Orthoclasehttp://en.wikipedia.org/wiki/Quartzhttp://en.wikipedia.org/wiki/Quartzhttp://en.wikipedia.org/wiki/Topazhttp://en.wikipedia.org/wiki/Topazhttp://en.wikipedia.org/wiki/Corundumhttp://en.wikipedia.org/wiki/Corundumhttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Luster_(mineralogy)http://en.wikipedia.org/wiki/Luster_(mineralogy)http://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Pyritehttp://en.wikipedia.org/wiki/Pyritehttp://en.wikipedia.org/wiki/Pyritehttp://en.wikipedia.org/wiki/Magnetitehttp://en.wikipedia.org/wiki/Magnetitehttp://en.wikipedia.org/wiki/Magnetitehttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Cerussitehttp://en.wikipedia.org/wiki/Cerussitehttp://en.wikipedia.org/wiki/Cerussitehttp://en.wikipedia.org/wiki/Anglesitehttp://en.wikipedia.org/wiki/Anglesitehttp://en.wikipedia.org/wiki/Anglesitehttp://en.wikipedia.org/wiki/Apophyllitehttp://en.wikipedia.org/wiki/Apophyllitehttp://en.wikipedia.org/wiki/Apophyllitehttp://en.wikipedia.org/wiki/Sphaleritehttp://en.wikipedia.org/wiki/Sphaleritehttp://en.wikipedia.org/wiki/Sphaleritehttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Chrysotilehttp://en.wikipedia.org/wiki/Chrysotilehttp://en.wikipedia.org/wiki/Chrysotilehttp://en.wikipedia.org/wiki/Hematitehttp://en.wikipedia.org/wiki/Hematitehttp://en.wikipedia.org/wiki/Hematitehttp://en.wikipedia.org/wiki/File:Rough_diamond.jpghttp://en.wikipedia.org/wiki/File:Rough_diamond.jpghttp://en.wikipedia.org/wiki/File:Talc_block.jpghttp://en.wikipedia.org/wiki/File:Talc_block.jpghttp://en.wikipedia.org/wiki/File:Rough_diamond.jpghttp://en.wikipedia.org/wiki/File:Rough_diamond.jpghttp://en.wikipedia.org/wiki/File:Talc_block.jpghttp://en.wikipedia.org/wiki/File:Talc_block.jpghttp://en.wikipedia.org/wiki/File:Rough_diamond.jpghttp://en.wikipedia.org/wiki/File:Rough_diamond.jpghttp://en.wikipedia.org/wiki/File:Talc_block.jpghttp://en.wikipedia.org/wiki/File:Talc_block.jpghttp://en.wikipedia.org/wiki/File:Rough_diamond.jpghttp://en.wikipedia.org/wiki/File:Rough_diamond.jpghttp://en.wikipedia.org/wiki/File:Talc_block.jpghttp://en.wikipedia.org/wiki/File:Talc_block.jpghttp://en.wikipedia.org/wiki/Hematitehttp://en.wikipedia.org/wiki/Chrysotilehttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Sphaleritehttp://en.wikipedia.org/wiki/Apophyllitehttp://en.wikipedia.org/wiki/Anglesitehttp://en.wikipedia.org/wiki/Cerussitehttp://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Magnetitehttp://en.wikipedia.org/wiki/Pyritehttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Luster_(mineralogy)http://en.wikipedia.org/wiki/Diamondhttp://en.wikipedia.org/wiki/Corundumhttp://en.wikipedia.org/wiki/Topazhttp://en.wikipedia.org/wiki/Quartzhttp://en.wikipedia.org/wiki/Orthoclasehttp://en.wikipedia.org/wiki/Apatitehttp://en.wikipedia.org/wiki/Fluoritehttp://en.wikipedia.org/wiki/Calcitehttp://en.wikipedia.org/wiki/Gypsumhttp://en.wikipedia.org/wiki/Talchttp://en.wikipedia.org/wiki/Mineral#cite_note-24http://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardnesshttp://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardnesshttp://en.wikipedia.org/wiki/Hardness_(materials_science)7/31/2019 7 Earth Materials
5/37
5 | P a g e
Diaphaneitydescribes how well light passes through a mineral; there are three basic degrees of
transparency:
Transparentobjects can be seen through a transparent mineral, such as a clear quartz
crystal
Translucentlight passes through the mineral but no objects can be seen
Opaqueno light passes through the mineral
Many minerals range from transparent to translucent or translucent to opaque. Calcite, for
instance, can be translucent or opaque. Some minerals that are naturally translucent become
opaque with weathering.
Colorindicates the appearance of the mineral in reflected light or transmitted light for
translucent minerals (i.e. what it looks like to the naked eye).
Iridescence the play of colorsdue to surface or internal
interference.Labradoriteexhibits internal iridescence whereas hematite and sphalerite
often show the surface effect.
Streakrefers to the color of the powder a mineral leaves after rubbing it on an unglazed
porcelain streak plate. Note that this is not always the same color as the original mineral.
Cleavagedescribes the way a mineral may split apart along various planes. In thin sections,
cleavage is visible as thin parallel lines across a mineral.
Fracturedescribes how a mineral breaks when broken contrary to its natural cleavage planes.
Chonchoidal fractureis a smooth curved fracture with concentric ridges of the type
shown by glass.
Hackleyis jagged fracture with sharp edges.
Fibrous
Irregular
Specific gravityrelates the mineralmassto the mass of an equal volume of water, namely
thedensityof the material. While most minerals, including all the common rock-forming
minerals, have a specific gravity of 2.53.5, a few are noticeably more or less dense, e.g.
several sulfide minerals have high specific gravity compared to the common rock-forming
minerals.
Other properties:fluorescence(response to ultraviolet
light),magnetism,radioactivity,tenacity(response to mechanical induced changes of shapeor form),piezoelectricityand reactivity to diluteacids.
Chemical properties of minerals
Minerals may be classified according to chemical composition. They are here categorized
byaniongroup. The list below is in approximate order of their abundance in the Earth'scrust. The
list follows theDanaclassification system[1][26]
which closely parallels theStrunz classification.
http://en.wikipedia.org/wiki/Diaphaneityhttp://en.wikipedia.org/wiki/Diaphaneityhttp://en.wikipedia.org/wiki/Colorhttp://en.wikipedia.org/wiki/Colorhttp://en.wikipedia.org/wiki/Labradoritehttp://en.wikipedia.org/wiki/Labradoritehttp://en.wikipedia.org/wiki/Labradoritehttp://en.wikipedia.org/wiki/Streak_(mineralogy)http://en.wikipedia.org/wiki/Streak_(mineralogy)http://en.wikipedia.org/wiki/Cleavage_(crystal)http://en.wikipedia.org/wiki/Cleavage_(crystal)http://en.wikipedia.org/wiki/Fracture_(mineralogy)http://en.wikipedia.org/wiki/Fracture_(mineralogy)http://en.wikipedia.org/wiki/Specific_gravityhttp://en.wikipedia.org/wiki/Specific_gravityhttp://en.wikipedia.org/wiki/Masshttp://en.wikipedia.org/wiki/Masshttp://en.wikipedia.org/wiki/Masshttp://en.wikipedia.org/wiki/Densityhttp://en.wikipedia.org/wiki/Densityhttp://en.wikipedia.org/wiki/Densityhttp://en.wikipedia.org/wiki/Fluorescencehttp://en.wikipedia.org/wiki/Fluorescencehttp://en.wikipedia.org/wiki/Fluorescencehttp://en.wikipedia.org/wiki/Magnetismhttp://en.wikipedia.org/wiki/Magnetismhttp://en.wikipedia.org/wiki/Magnetismhttp://en.wikipedia.org/wiki/Radioactivityhttp://en.wikipedia.org/wiki/Radioactivityhttp://en.wikipedia.org/wiki/Radioactivityhttp://en.wikipedia.org/w/index.php?title=Tenacity_(geology)&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Tenacity_(geology)&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Tenacity_(geology)&action=edit&redlink=1http://en.wikipedia.org/wiki/Piezoelectricityhttp://en.wikipedia.org/wiki/Piezoelectricityhttp://en.wikipedia.org/wiki/Piezoelectricityhttp://en.wikipedia.org/wiki/Acidhttp://en.wikipedia.org/wiki/Acidhttp://en.wikipedia.org/wiki/Acidhttp://en.wikipedia.org/wiki/Anionhttp://en.wikipedia.org/wiki/Anionhttp://en.wikipedia.org/wiki/Anionhttp://en.wikipedia.org/wiki/Crust_(geology)http://en.wikipedia.org/wiki/Crust_(geology)http://en.wikipedia.org/wiki/Crust_(geology)http://en.wikipedia.org/wiki/James_Dwight_Danahttp://en.wikipedia.org/wiki/James_Dwight_Danahttp://en.wikipedia.org/wiki/James_Dwight_Danahttp://en.wikipedia.org/wiki/Mineral#cite_note-Klein-0http://en.wikipedia.org/wiki/Mineral#cite_note-Klein-0http://en.wikipedia.org/wiki/Strunz_classificationhttp://en.wikipedia.org/wiki/Strunz_classificationhttp://en.wikipedia.org/wiki/Strunz_classificationhttp://en.wikipedia.org/wiki/Strunz_classificationhttp://en.wikipedia.org/wiki/Mineral#cite_note-Klein-0http://en.wikipedia.org/wiki/Mineral#cite_note-Klein-0http://en.wikipedia.org/wiki/James_Dwight_Danahttp://en.wikipedia.org/wiki/Crust_(geology)http://en.wikipedia.org/wiki/Anionhttp://en.wikipedia.org/wiki/Acidhttp://en.wikipedia.org/wiki/Piezoelectricityhttp://en.wikipedia.org/w/index.php?title=Tenacity_(geology)&action=edit&redlink=1http://en.wikipedia.org/wiki/Radioactivityhttp://en.wikipedia.org/wiki/Magnetismhttp://en.wikipedia.org/wiki/Fluorescencehttp://en.wikipedia.org/wiki/Densityhttp://en.wikipedia.org/wiki/Masshttp://en.wikipedia.org/wiki/Specific_gravityhttp://en.wikipedia.org/wiki/Fracture_(mineralogy)http://en.wikipedia.org/wiki/Cleavage_(crystal)http://en.wikipedia.org/wiki/Streak_(mineralogy)http://en.wikipedia.org/wiki/Labradoritehttp://en.wikipedia.org/wiki/Colorhttp://en.wikipedia.org/wiki/Diaphaneity7/31/2019 7 Earth Materials
6/37
6 | P a g e
Silicate class
Quartz
The largest group of minerals by far are thesilicates(most rocks are 95% silicates), which are
composed largely ofsiliconandoxygen, with the addition of ions such
asaluminium,magnesium,iron, andcalcium. Some important rock-forming silicates include
thefeldspars,quartz,olivines,pyroxenes,amphiboles,garnets, andmicas.
Carbonate class
Thecarbonate mineralsconsist of those minerals containing the anion (CO3)2
and
includecalciteandaragonite(both calcium carbonate),dolomite(magnesium/calcium carbonate)
andsiderite(iron carbonate). Carbonates are commonly deposited in marine settings when the
shells of deadplanktoniclife settle and accumulate on the sea floor. Carbonates are also found
inevaporiticsettings (e.g. theGreat Salt Lake,Utah) and also inkarstregions, where the
dissolution and reprecipitation of carbonates leads to the formation
ofcaves,stalactitesandstalagmites. The carbonate class also includes thenitrateandborate
minerals.
Sulfate class
Hanksite, Na22K(SO4)9(CO3)2Cl, one of the few minerals that is considered a carbonate and a sulfate
Sulfate mineralsall contain the sulfate anion, SO42
. Sulfates commonly form
inevaporiticsettings where highly saline waters slowly evaporate, allowing the formation of bothsulfates and halides at the water-sediment interface. Sulfates also occur inhydrothermalvein
http://en.wikipedia.org/wiki/Quartzhttp://en.wikipedia.org/wiki/Quartzhttp://en.wikipedia.org/wiki/Silicate_mineralshttp://en.wikipedia.org/wiki/Silicate_mineralshttp://en.wikipedia.org/wiki/Silicate_mineralshttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Aluminiumhttp://en.wikipedia.org/wiki/Aluminiumhttp://en.wikipedia.org/wiki/Aluminiumhttp://en.wikipedia.org/wiki/Magnesiumhttp://en.wikipedia.org/wiki/Magnesiumhttp://en.wikipedia.org/wiki/Magnesiumhttp://en.wikipedia.org/wiki/Ironhttp://en.wikipedia.org/wiki/Ironhttp://en.wikipedia.org/wiki/Ironhttp://en.wikipedia.org/wiki/Calciumhttp://en.wikipedia.org/wiki/Calciumhttp://en.wikipedia.org/wiki/Calciumhttp://en.wikipedia.org/wiki/Feldsparhttp://en.wikipedia.org/wiki/Feldsparhttp://en.wikipedia.org/wiki/Feldsparhttp://en.wikipedia.org/wiki/Quartzhttp://en.wikipedia.org/wiki/Quartzhttp://en.wikipedia.org/wiki/Olivinehttp://en.wikipedia.org/wiki/Olivinehttp://en.wikipedia.org/wiki/Olivinehttp://en.wikipedia.org/wiki/Pyroxenehttp://en.wikipedia.org/wiki/Pyroxenehttp://en.wikipedia.org/wiki/Pyroxenehttp://en.wikipedia.org/wiki/Amphibolehttp://en.wikipedia.org/wiki/Amphibolehttp://en.wikipedia.org/wiki/Amphibolehttp://en.wikipedia.org/wiki/Garnethttp://en.wikipedia.org/wiki/Garnethttp://en.wikipedia.org/wiki/Garnethttp://en.wikipedia.org/wiki/Micahttp://en.wikipedia.org/wiki/Micahttp://en.wikipedia.org/wiki/Micahttp://en.wikipedia.org/wiki/Carbonate_mineralshttp://en.wikipedia.org/wiki/Carbonate_mineralshttp://en.wikipedia.org/wiki/Carbonate_mineralshttp://en.wikipedia.org/wiki/Calcitehttp://en.wikipedia.org/wiki/Calcitehttp://en.wikipedia.org/wiki/Calcitehttp://en.wikipedia.org/wiki/Aragonitehttp://en.wikipedia.org/wiki/Aragonitehttp://en.wikipedia.org/wiki/Aragonitehttp://en.wikipedia.org/wiki/Dolomitehttp://en.wikipedia.org/wiki/Dolomitehttp://en.wikipedia.org/wiki/Dolomitehttp://en.wikipedia.org/wiki/Sideritehttp://en.wikipedia.org/wiki/Sideritehttp://en.wikipedia.org/wiki/Sideritehttp://en.wikipedia.org/wiki/Planktonhttp://en.wikipedia.org/wiki/Planktonhttp://en.wikipedia.org/wiki/Planktonhttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Great_Salt_Lakehttp://en.wikipedia.org/wiki/Great_Salt_Lakehttp://en.wikipedia.org/wiki/Great_Salt_Lakehttp://en.wikipedia.org/wiki/Utahhttp://en.wikipedia.org/wiki/Utahhttp://en.wikipedia.org/wiki/Utahhttp://en.wikipedia.org/wiki/Karsthttp://en.wikipedia.org/wiki/Karsthttp://en.wikipedia.org/wiki/Karsthttp://en.wikipedia.org/wiki/Cavehttp://en.wikipedia.org/wiki/Cavehttp://en.wikipedia.org/wiki/Cavehttp://en.wikipedia.org/wiki/Stalactitehttp://en.wikipedia.org/wiki/Stalactitehttp://en.wikipedia.org/wiki/Stalactitehttp://en.wikipedia.org/wiki/Stalagmitehttp://en.wikipedia.org/wiki/Stalagmitehttp://en.wikipedia.org/wiki/Stalagmitehttp://en.wikipedia.org/wiki/Nitratehttp://en.wikipedia.org/wiki/Nitratehttp://en.wikipedia.org/wiki/Nitratehttp://en.wikipedia.org/wiki/Borate_mineralhttp://en.wikipedia.org/wiki/Borate_mineralhttp://en.wikipedia.org/wiki/Borate_mineralhttp://en.wikipedia.org/wiki/Borate_mineralhttp://en.wikipedia.org/wiki/Hanksitehttp://en.wikipedia.org/wiki/Hanksitehttp://en.wikipedia.org/wiki/Sulfate_mineralhttp://en.wikipedia.org/wiki/Sulfate_mineralhttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Hydrothermalhttp://en.wikipedia.org/wiki/Hydrothermalhttp://en.wikipedia.org/wiki/Hydrothermalhttp://en.wikipedia.org/wiki/File:Hanksite.JPGhttp://en.wikipedia.org/wiki/File:Hanksite.JPGhttp://en.wikipedia.org/wiki/File:Quartz,_Tibet.jpghttp://en.wikipedia.org/wiki/File:Quartz,_Tibet.jpghttp://en.wikipedia.org/wiki/File:Hanksite.JPGhttp://en.wikipedia.org/wiki/File:Hanksite.JPGhttp://en.wikipedia.org/wiki/File:Quartz,_Tibet.jpghttp://en.wikipedia.org/wiki/File:Quartz,_Tibet.jpghttp://en.wikipedia.org/wiki/File:Hanksite.JPGhttp://en.wikipedia.org/wiki/File:Hanksite.JPGhttp://en.wikipedia.org/wiki/File:Quartz,_Tibet.jpghttp://en.wikipedia.org/wiki/File:Quartz,_Tibet.jpghttp://en.wikipedia.org/wiki/File:Hanksite.JPGhttp://en.wikipedia.org/wiki/File:Hanksite.JPGhttp://en.wikipedia.org/wiki/File:Quartz,_Tibet.jpghttp://en.wikipedia.org/wiki/File:Quartz,_Tibet.jpghttp://en.wikipedia.org/wiki/Hydrothermalhttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Sulfate_mineralhttp://en.wikipedia.org/wiki/Hanksitehttp://en.wikipedia.org/wiki/Borate_mineralhttp://en.wikipedia.org/wiki/Borate_mineralhttp://en.wikipedia.org/wiki/Nitratehttp://en.wikipedia.org/wiki/Stalagmitehttp://en.wikipedia.org/wiki/Stalactitehttp://en.wikipedia.org/wiki/Cavehttp://en.wikipedia.org/wiki/Karsthttp://en.wikipedia.org/wiki/Utahhttp://en.wikipedia.org/wiki/Great_Salt_Lakehttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Planktonhttp://en.wikipedia.org/wiki/Sideritehttp://en.wikipedia.org/wiki/Dolomitehttp://en.wikipedia.org/wiki/Aragonitehttp://en.wikipedia.org/wiki/Calcitehttp://en.wikipedia.org/wiki/Carbonate_mineralshttp://en.wikipedia.org/wiki/Micahttp://en.wikipedia.org/wiki/Garnethttp://en.wikipedia.org/wiki/Amphibolehttp://en.wikipedia.org/wiki/Pyroxenehttp://en.wikipedia.org/wiki/Olivinehttp://en.wikipedia.org/wiki/Quartzhttp://en.wikipedia.org/wiki/Feldsparhttp://en.wikipedia.org/wiki/Calciumhttp://en.wikipedia.org/wiki/Ironhttp://en.wikipedia.org/wiki/Magnesiumhttp://en.wikipedia.org/wiki/Aluminiumhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Siliconhttp://en.wikipedia.org/wiki/Silicate_mineralshttp://en.wikipedia.org/wiki/Quartz7/31/2019 7 Earth Materials
7/37
7 | P a g e
systems as gangue minerals along withsulfideoreminerals. Another occurrence is as
secondaryoxidationproducts of original sulfide minerals. Common sulfates
includeanhydrite(calcium sulfate),celestine(strontium sulfate),barite(barium sulfate),
andgypsum(hydrated calcium sulfate). The sulfate class also includes
thechromate,molybdate,selenate,sulfite,tellurate, andtungstateminerals.
Halide class
Halite
Thehalide mineralsare the group of minerals forming the naturalsaltsand
includefluorite(calcium fluoride),halite(sodium chloride),sylvite(potassium chloride), andsal
ammoniac(ammonium chloride). Halides, like sulfates, are commonly found inevaporitesettings
such assalt lakesand landlocked seas such as theDead SeaandGreat Salt Lake. The halide
class includes thefluoride,chloride,bromideandiodideminerals.
Oxide class
Oxide mineralsare extremely important inminingas they form many of theoresfrom which
valuable metals can be extracted. They also carry the best record of changes in theEarth's
magnetic field. They commonly occur as precipitates close to the Earth's
surface,oxidationproducts of other minerals in the near surfaceweatheringzone, and as
accessory minerals in igneous rocks of the crust andmantle. Common oxides
includehematite(iron oxide),magnetite(iron oxide),chromite(iron chromium
oxide),spinel(magnesium aluminium oxide a common component of the mantle),ilmenite(iron
titanium oxide),rutile(titanium dioxide), andice(hydrogen oxide). The oxide class includes the
oxide and thehydroxideminerals.
Sulfide class
Manysulfide mineralsare economically important as metalores. Common sulfides
includepyrite(iron sulfide commonly known as fools' gold),chalcopyrite(copper iron
sulfide),pentlandite(nickel iron sulfide), andgalena(lead sulfide). The sulfide class also includes
theselenides, thetellurides, thearsenides, theantimonides, the bismuthinides, and
thesulfosalts(sulfur and a second anion such as arsenic).
Phosphate class
Thephosphate mineralgroup actually includes any mineral with a tetrahedral unit AO4 where A
can bephosphorus,antimony,arsenicorvanadium. By far the most common phosphate
http://en.wikipedia.org/wiki/Sulfidehttp://en.wikipedia.org/wiki/Sulfidehttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Oxidationhttp://en.wikipedia.org/wiki/Oxidationhttp://en.wikipedia.org/wiki/Oxidationhttp://en.wikipedia.org/wiki/Anhydritehttp://en.wikipedia.org/wiki/Anhydritehttp://en.wikipedia.org/wiki/Anhydritehttp://en.wikipedia.org/wiki/Calcium_sulfatehttp://en.wikipedia.org/wiki/Calcium_sulfatehttp://en.wikipedia.org/wiki/Calcium_sulfatehttp://en.wikipedia.org/wiki/Celestine_(mineral)http://en.wikipedia.org/wiki/Celestine_(mineral)http://en.wikipedia.org/wiki/Celestine_(mineral)http://en.wikipedia.org/wiki/Baritehttp://en.wikipedia.org/wiki/Baritehttp://en.wikipedia.org/wiki/Baritehttp://en.wikipedia.org/wiki/Gypsumhttp://en.wikipedia.org/wiki/Gypsumhttp://en.wikipedia.org/wiki/Gypsumhttp://en.wikipedia.org/wiki/Chromatehttp://en.wikipedia.org/wiki/Chromatehttp://en.wikipedia.org/wiki/Chromatehttp://en.wikipedia.org/wiki/Molybdatehttp://en.wikipedia.org/wiki/Molybdatehttp://en.wikipedia.org/wiki/Molybdatehttp://en.wikipedia.org/wiki/Selenatehttp://en.wikipedia.org/wiki/Selenatehttp://en.wikipedia.org/wiki/Selenatehttp://en.wikipedia.org/wiki/Sulfitehttp://en.wikipedia.org/wiki/Sulfitehttp://en.wikipedia.org/wiki/Sulfitehttp://en.wikipedia.org/wiki/Telluratehttp://en.wikipedia.org/wiki/Telluratehttp://en.wikipedia.org/wiki/Telluratehttp://en.wikipedia.org/wiki/Tungstatehttp://en.wikipedia.org/wiki/Tungstatehttp://en.wikipedia.org/wiki/Tungstatehttp://en.wikipedia.org/wiki/Halitehttp://en.wikipedia.org/wiki/Halitehttp://en.wikipedia.org/wiki/Halide_mineralhttp://en.wikipedia.org/wiki/Halide_mineralhttp://en.wikipedia.org/wiki/Halide_mineralhttp://en.wikipedia.org/wiki/Salthttp://en.wikipedia.org/wiki/Salthttp://en.wikipedia.org/wiki/Salthttp://en.wikipedia.org/wiki/Fluoritehttp://en.wikipedia.org/wiki/Fluoritehttp://en.wikipedia.org/wiki/Fluoritehttp://en.wikipedia.org/wiki/Halitehttp://en.wikipedia.org/wiki/Halitehttp://en.wikipedia.org/wiki/Halitehttp://en.wikipedia.org/wiki/Sylvitehttp://en.wikipedia.org/wiki/Sylvitehttp://en.wikipedia.org/wiki/Sylvitehttp://en.wikipedia.org/wiki/Sal_ammoniachttp://en.wikipedia.org/wiki/Sal_ammoniachttp://en.wikipedia.org/wiki/Sal_ammoniachttp://en.wikipedia.org/wiki/Sal_ammoniachttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Salt_lakehttp://en.wikipedia.org/wiki/Salt_lakehttp://en.wikipedia.org/wiki/Salt_lakehttp://en.wikipedia.org/wiki/Dead_Seahttp://en.wikipedia.org/wiki/Dead_Seahttp://en.wikipedia.org/wiki/Dead_Seahttp://en.wikipedia.org/wiki/Great_Salt_Lakehttp://en.wikipedia.org/wiki/Great_Salt_Lakehttp://en.wikipedia.org/wiki/Great_Salt_Lakehttp://en.wikipedia.org/wiki/Fluoridehttp://en.wikipedia.org/wiki/Fluoridehttp://en.wikipedia.org/wiki/Fluoridehttp://en.wikipedia.org/wiki/Chloridehttp://en.wikipedia.org/wiki/Chloridehttp://en.wikipedia.org/wiki/Chloridehttp://en.wikipedia.org/wiki/Bromidehttp://en.wikipedia.org/wiki/Bromidehttp://en.wikipedia.org/wiki/Bromidehttp://en.wikipedia.org/wiki/Iodidehttp://en.wikipedia.org/wiki/Iodidehttp://en.wikipedia.org/wiki/Oxide_mineralhttp://en.wikipedia.org/wiki/Oxide_mineralhttp://en.wikipedia.org/wiki/Mininghttp://en.wikipedia.org/wiki/Mininghttp://en.wikipedia.org/wiki/Mininghttp://en.wikipedia.org/wiki/Oreshttp://en.wikipedia.org/wiki/Oreshttp://en.wikipedia.org/wiki/Oreshttp://en.wikipedia.org/wiki/Earth%27s_magnetic_fieldhttp://en.wikipedia.org/wiki/Earth%27s_magnetic_fieldhttp://en.wikipedia.org/wiki/Earth%27s_magnetic_fieldhttp://en.wikipedia.org/wiki/Earth%27s_magnetic_fieldhttp://en.wikipedia.org/wiki/Oxidationhttp://en.wikipedia.org/wiki/Oxidationhttp://en.wikipedia.org/wiki/Oxidationhttp://en.wikipedia.org/wiki/Weatheringhttp://en.wikipedia.org/wiki/Weatheringhttp://en.wikipedia.org/wiki/Weatheringhttp://en.wikipedia.org/wiki/Mantle_(geology)http://en.wikipedia.org/wiki/Mantle_(geology)http://en.wikipedia.org/wiki/Mantle_(geology)http://en.wikipedia.org/wiki/Hematitehttp://en.wikipedia.org/wiki/Hematitehttp://en.wikipedia.org/wiki/Hematitehttp://en.wikipedia.org/wiki/Magnetitehttp://en.wikipedia.org/wiki/Magnetitehttp://en.wikipedia.org/wiki/Magnetitehttp://en.wikipedia.org/wiki/Chromitehttp://en.wikipedia.org/wiki/Chromitehttp://en.wikipedia.org/wiki/Chromitehttp://en.wikipedia.org/wiki/Spinelhttp://en.wikipedia.org/wiki/Spinelhttp://en.wikipedia.org/wiki/Spinelhttp://en.wikipedia.org/wiki/Ilmenitehttp://en.wikipedia.org/wiki/Ilmenitehttp://en.wikipedia.org/wiki/Ilmenitehttp://en.wikipedia.org/wiki/Rutilehttp://en.wikipedia.org/wiki/Rutilehttp://en.wikipedia.org/wiki/Rutilehttp://en.wikipedia.org/wiki/Icehttp://en.wikipedia.org/wiki/Icehttp://en.wikipedia.org/wiki/Icehttp://en.wikipedia.org/wiki/Hydroxidehttp://en.wikipedia.org/wiki/Hydroxidehttp://en.wikipedia.org/wiki/Hydroxidehttp://en.wikipedia.org/wiki/Sulfide_mineralhttp://en.wikipedia.org/wiki/Sulfide_mineralhttp://en.wikipedia.org/wiki/Sulfide_mineralhttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Pyritehttp://en.wikipedia.org/wiki/Pyritehttp://en.wikipedia.org/wiki/Pyritehttp://en.wikipedia.org/wiki/Chalcopyritehttp://en.wikipedia.org/wiki/Chalcopyritehttp://en.wikipedia.org/wiki/Chalcopyritehttp://en.wikipedia.org/wiki/Pentlanditehttp://en.wikipedia.org/wiki/Pentlanditehttp://en.wikipedia.org/wiki/Pentlanditehttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Selenidehttp://en.wikipedia.org/wiki/Selenidehttp://en.wikipedia.org/wiki/Selenidehttp://en.wikipedia.org/wiki/Telluride_(chemistry)http://en.wikipedia.org/wiki/Telluride_(chemistry)http://en.wikipedia.org/wiki/Telluride_(chemistry)http://en.wikipedia.org/wiki/Arsenidehttp://en.wikipedia.org/wiki/Arsenidehttp://en.wikipedia.org/wiki/Arsenidehttp://en.wikipedia.org/wiki/Antimonidehttp://en.wikipedia.org/wiki/Antimonidehttp://en.wikipedia.org/wiki/Antimonidehttp://en.wikipedia.org/wiki/Sulfosalthttp://en.wikipedia.org/wiki/Sulfosalthttp://en.wikipedia.org/wiki/Sulfosalthttp://en.wikipedia.org/wiki/Phosphate_mineralhttp://en.wikipedia.org/wiki/Phosphate_mineralhttp://en.wikipedia.org/wiki/Phosphate_mineralhttp://en.wikipedia.org/wiki/Phosphorushttp://en.wikipedia.org/wiki/Phosphorushttp://en.wikipedia.org/wiki/Phosphorushttp://en.wikipedia.org/wiki/Antimonyhttp://en.wikipedia.org/wiki/Antimonyhttp://en.wikipedia.org/wiki/Antimonyhttp://en.wikipedia.org/wiki/Arsenichttp://en.wikipedia.org/wiki/Arsenichttp://en.wikipedia.org/wiki/Arsenichttp://en.wikipedia.org/wiki/Vanadiumhttp://en.wikipedia.org/wiki/Vanadiumhttp://en.wikipedia.org/wiki/Vanadiumhttp://en.wikipedia.org/wiki/File:Halite(Salt)USGOV.jpghttp://en.wikipedia.org/wiki/File:Halite(Salt)USGOV.jpghttp://en.wikipedia.org/wiki/File:Halite(Salt)USGOV.jpghttp://en.wikipedia.org/wiki/File:Halite(Salt)USGOV.jpghttp://en.wikipedia.org/wiki/Vanadiumhttp://en.wikipedia.org/wiki/Arsenichttp://en.wikipedia.org/wiki/Antimonyhttp://en.wikipedia.org/wiki/Phosphorushttp://en.wikipedia.org/wiki/Phosphate_mineralhttp://en.wikipedia.org/wiki/Sulfosalthttp://en.wikipedia.org/wiki/Antimonidehttp://en.wikipedia.org/wiki/Arsenidehttp://en.wikipedia.org/wiki/Telluride_(chemistry)http://en.wikipedia.org/wiki/Selenidehttp://en.wikipedia.org/wiki/Galenahttp://en.wikipedia.org/wiki/Pentlanditehttp://en.wikipedia.org/wiki/Chalcopyritehttp://en.wikipedia.org/wiki/Pyritehttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Sulfide_mineralhttp://en.wikipedia.org/wiki/Hydroxidehttp://en.wikipedia.org/wiki/Icehttp://en.wikipedia.org/wiki/Rutilehttp://en.wikipedia.org/wiki/Ilmenitehttp://en.wikipedia.org/wiki/Spinelhttp://en.wikipedia.org/wiki/Chromitehttp://en.wikipedia.org/wiki/Magnetitehttp://en.wikipedia.org/wiki/Hematitehttp://en.wikipedia.org/wiki/Mantle_(geology)http://en.wikipedia.org/wiki/Weatheringhttp://en.wikipedia.org/wiki/Oxidationhttp://en.wikipedia.org/wiki/Earth%27s_magnetic_fieldhttp://en.wikipedia.org/wiki/Earth%27s_magnetic_fieldhttp://en.wikipedia.org/wiki/Oreshttp://en.wikipedia.org/wiki/Mininghttp://en.wikipedia.org/wiki/Oxide_mineralhttp://en.wikipedia.org/wiki/Iodidehttp://en.wikipedia.org/wiki/Bromidehttp://en.wikipedia.org/wiki/Chloridehttp://en.wikipedia.org/wiki/Fluoridehttp://en.wikipedia.org/wiki/Great_Salt_Lakehttp://en.wikipedia.org/wiki/Dead_Seahttp://en.wikipedia.org/wiki/Salt_lakehttp://en.wikipedia.org/wiki/Evaporitehttp://en.wikipedia.org/wiki/Sal_ammoniachttp://en.wikipedia.org/wiki/Sal_ammoniachttp://en.wikipedia.org/wiki/Sylvitehttp://en.wikipedia.org/wiki/Halitehttp://en.wikipedia.org/wiki/Fluoritehttp://en.wikipedia.org/wiki/Salthttp://en.wikipedia.org/wiki/Halide_mineralhttp://en.wikipedia.org/wiki/Halitehttp://en.wikipedia.org/wiki/Tungstatehttp://en.wikipedia.org/wiki/Telluratehttp://en.wikipedia.org/wiki/Sulfitehttp://en.wikipedia.org/wiki/Selenatehttp://en.wikipedia.org/wiki/Molybdatehttp://en.wikipedia.org/wiki/Chromatehttp://en.wikipedia.org/wiki/Gypsumhttp://en.wikipedia.org/wiki/Baritehttp://en.wikipedia.org/wiki/Celestine_(mineral)http://en.wikipedia.org/wiki/Calcium_sulfatehttp://en.wikipedia.org/wiki/Anhydritehttp://en.wikipedia.org/wiki/Oxidationhttp://en.wikipedia.org/wiki/Orehttp://en.wikipedia.org/wiki/Sulfide7/31/2019 7 Earth Materials
8/37
8 | P a g e
isapatitewhich is an importantbiologicalmineral found in teeth and bones of many animals. The
phosphate class includes the phosphate,arsenate,vanadate, andantimonateminerals.
Element class
The elemental group includesnative metalsandintermetallicelements
(gold,silver,copper),semi-metalsandnon-metals(antimony,bismuth,graphite,sulfur). Thisgroup also includes naturalalloys, such aselectrum(a natural alloy of gold and
silver),phosphides,silicides,nitridesandcarbides(which are usually only found naturally in a few
raremeteorites).
Organic class
The organic mineral class includesbiogenicsubstances in which geological processes have been
a part of the genesis or origin of the existing compound.[2]
Minerals of the organic class include
variousoxalates,mellitates,citrates,cyanates,acetates,formates,hydrocarbonsand other
miscellaneous species.[5]
Examples
includewhewellite,moolooite,mellite,fichtelite,carpathite,evenkiteandabelsonite.
rocks
There are three kinds of rocks that can be found on Earth. These rocks are the Igneous,the Sedimentary and the Metamorphic rocks. These kinds ofrocks differ from their origin.
The Igneous rock is formed from the cooling and hardening of themoltenmaterials that are found in the crust, either closer to the surface or near avolcano. This kind of rock is the most abundant rock on the planet, comprising about
65% of allthe rocks.
Igneous is hard and tough, this rock are further divided into two groups; the extrusiveigneous rock and the intrusive igneous rock.
The common igneous rocks are the Diorite, the Andesite, the Granite, the Gabbro, theObsidian and the Basalt.
Diorite is a coarse-grained and generally light-colored rock. It is a kind of intrusive rockthat cools very slowly. Andesite is a fine-grained and light-colored extrusive rock and itis formed in the lava flows. Granite is a light-colored usually in gray or in pink and
coarse-grained rock and made up of several kinds of crystals. The Gabbro is a kind of acoarse-grained rock and it is often called as the black granite. The Obsidian is a dark-glassy this rock has no crystals. The Basalt is a dark and fine-grained rock that is formedfrom the lava or magma near the surface of the Earth.
The extrusive igneous rock is formed when the magma reach thesurface and hardens. Itis generally dark in color and heavy. This is because the extrusive igneous rock is reachin magnesium as well as in iron.
The intrusive igneous rock is formed when the magma finds its way to the crust but doesnot reach the surface. It cools slowly and takes thousands or millions of years to harden.The intrusive igneous rock is generally light-colored; it is rich in silica and it has a large
crystals. The igneous rock that has a big crystals are described as coarse-grained; whilethe igneous rock that has small crystals are described as fine-grained.
http://en.wikipedia.org/wiki/Apatitehttp://en.wikipedia.org/wiki/Apatitehttp://en.wikipedia.org/wiki/Apatitehttp://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Arsenatehttp://en.wikipedia.org/wiki/Arsenatehttp://en.wikipedia.org/wiki/Arsenatehttp://en.wikipedia.org/wiki/Vanadatehttp://en.wikipedia.org/wiki/Vanadatehttp://en.wikipedia.org/wiki/Vanadatehttp://en.wikipedia.org/wiki/Antimonatehttp://en.wikipedia.org/wiki/Antimonatehttp://en.wikipedia.org/wiki/Antimonatehttp://en.wikipedia.org/wiki/Native_metalhttp://en.wikipedia.org/wiki/Native_metalhttp://en.wikipedia.org/wiki/Native_metalhttp://en.wikipedia.org/wiki/Intermetallichttp://en.wikipedia.org/wiki/Intermetallichttp://en.wikipedia.org/wiki/Intermetallichttp://en.wikipedia.org/wiki/Goldhttp://en.wikipedia.org/wiki/Goldhttp://en.wikipedia.org/wiki/Goldhttp://en.wikipedia.org/wiki/Silverhttp://en.wikipedia.org/wiki/Silverhttp://en.wikipedia.org/wiki/Silverhttp://en.wikipedia.org/wiki/Copperhttp://en.wikipedia.org/wiki/Copperhttp://en.wikipedia.org/wiki/Copperhttp://en.wikipedia.org/wiki/Semimetalhttp://en.wikipedia.org/wiki/Semimetalhttp://en.wikipedia.org/wiki/Semimetalhttp://en.wikipedia.org/wiki/Non-metalshttp://en.wikipedia.org/wiki/Non-metalshttp://en.wikipedia.org/wiki/Non-metalshttp://en.wikipedia.org/wiki/Antimonyhttp://en.wikipedia.org/wiki/Antimonyhttp://en.wikipedia.org/wiki/Antimonyhttp://en.wikipedia.org/wiki/Bismuthhttp://en.wikipedia.org/wiki/Bismuthhttp://en.wikipedia.org/wiki/Bismuthhttp://en.wikipedia.org/wiki/Graphitehttp://en.wikipedia.org/wiki/Graphitehttp://en.wikipedia.org/wiki/Graphitehttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Alloyshttp://en.wikipedia.org/wiki/Alloyshttp://en.wikipedia.org/wiki/Alloyshttp://en.wikipedia.org/wiki/Electrumhttp://en.wikipedia.org/wiki/Electrumhttp://en.wikipedia.org/wiki/Electrumhttp://en.wikipedia.org/wiki/Phosphideshttp://en.wikipedia.org/wiki/Phosphideshttp://en.wikipedia.org/wiki/Phosphideshttp://en.wikipedia.org/wiki/Silicidehttp://en.wikipedia.org/wiki/Silicidehttp://en.wikipedia.org/wiki/Silicidehttp://en.wikipedia.org/wiki/Nitrideshttp://en.wikipedia.org/wiki/Nitrideshttp://en.wikipedia.org/wiki/Nitrideshttp://en.wikipedia.org/wiki/Carbideshttp://en.wikipedia.org/wiki/Carbideshttp://en.wikipedia.org/wiki/Carbideshttp://en.wikipedia.org/wiki/Meteoriteshttp://en.wikipedia.org/wiki/Meteoriteshttp://en.wikipedia.org/wiki/Meteoriteshttp://en.wikipedia.org/wiki/Biogenichttp://en.wikipedia.org/wiki/Biogenichttp://en.wikipedia.org/wiki/Biogenichttp://en.wikipedia.org/wiki/Mineral#cite_note-Nickel-1http://en.wikipedia.org/wiki/Mineral#cite_note-Nickel-1http://en.wikipedia.org/wiki/Mineral#cite_note-Nickel-1http://en.wikipedia.org/wiki/Oxalateshttp://en.wikipedia.org/wiki/Oxalateshttp://en.wikipedia.org/wiki/Oxalateshttp://en.wikipedia.org/w/index.php?title=Mellitates&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Mellitates&action=edit&redlink=1http://en.wikipedia.org/w/index.php?title=Mellitates&action=edit&redlink=1http://en.wikipedia.org/wiki/Citrateshttp://en.wikipedia.org/wiki/Citrateshttp://en.wikipedia.org/wiki/Citrateshttp://en.wikipedia.org/wiki/Cyanatehttp://en.wikipedia.org/wiki/Cyanatehttp://en.wikipedia.org/wiki/Cyanatehttp://en.wikipedia.org/wiki/Acetateshttp://en.wikipedia.org/wiki/Acetateshttp://en.wikipedia.org/wiki/Acetateshttp://en.wikipedia.org/wiki/Formateshttp://en.wikipedia.org/wiki/Formateshttp://en.wikipedia.org/wiki/Formateshttp://en.wikipedia.org/wiki/Hydrocarbonshttp://en.wikipedia.org/wiki/Hydrocarbonshttp://en.wikipedia.org/wiki/Hydrocarbonshttp://en.wikipedia.org/wiki/Mineral#cite_note-Dana-4http://en.wikipedia.org/wiki/Mineral#cite_note-Dana-4http://en.wikipedia.org/wiki/Mineral#cite_note-Dana-4http://en.wikipedia.org/wiki/Whewellitehttp://en.wikipedia.org/wiki/Whewellitehttp://en.wikipedia.org/wiki/Whewellitehttp://en.wikipedia.org/wiki/Moolooitehttp://en.wikipedia.org/wiki/Moolooitehttp://en.wikipedia.org/wiki/Moolooitehttp://en.wikipedia.org/wiki/Mellitehttp://en.wikipedia.org/wiki/Mellitehttp://en.wikipedia.org/wiki/Mellitehttp://en.wikipedia.org/wiki/Fichtelitehttp://en.wikipedia.org/wiki/Fichtelitehttp://en.wikipedia.org/wiki/Carpathitehttp://en.wikipedia.org/wiki/Carpathitehttp://en.wikipedia.org/wiki/Carpathitehttp://en.wikipedia.org/wiki/Evenkitehttp://en.wikipedia.org/wiki/Evenkitehttp://en.wikipedia.org/wiki/Evenkitehttp://en.wikipedia.org/wiki/Abelsonitehttp://en.wikipedia.org/wiki/Abelsonitehttp://en.wikipedia.org/wiki/Abelsonitehttp://en.wikipedia.org/wiki/Abelsonitehttp://en.wikipedia.org/wiki/Evenkitehttp://en.wikipedia.org/wiki/Carpathitehttp://en.wikipedia.org/wiki/Fichtelitehttp://en.wikipedia.org/wiki/Mellitehttp://en.wikipedia.org/wiki/Moolooitehttp://en.wikipedia.org/wiki/Whewellitehttp://en.wikipedia.org/wiki/Mineral#cite_note-Dana-4http://en.wikipedia.org/wiki/Hydrocarbonshttp://en.wikipedia.org/wiki/Formateshttp://en.wikipedia.org/wiki/Acetateshttp://en.wikipedia.org/wiki/Cyanatehttp://en.wikipedia.org/wiki/Citrateshttp://en.wikipedia.org/w/index.php?title=Mellitates&action=edit&redlink=1http://en.wikipedia.org/wiki/Oxalateshttp://en.wikipedia.org/wiki/Mineral#cite_note-Nickel-1http://en.wikipedia.org/wiki/Biogenichttp://en.wikipedia.org/wiki/Meteoriteshttp://en.wikipedia.org/wiki/Carbideshttp://en.wikipedia.org/wiki/Nitrideshttp://en.wikipedia.org/wiki/Silicidehttp://en.wikipedia.org/wiki/Phosphideshttp://en.wikipedia.org/wiki/Electrumhttp://en.wikipedia.org/wiki/Alloyshttp://en.wikipedia.org/wiki/Sulfurhttp://en.wikipedia.org/wiki/Graphitehttp://en.wikipedia.org/wiki/Bismuthhttp://en.wikipedia.org/wiki/Antimonyhttp://en.wikipedia.org/wiki/Non-metalshttp://en.wikipedia.org/wiki/Semimetalhttp://en.wikipedia.org/wiki/Copperhttp://en.wikipedia.org/wiki/Silverhttp://en.wikipedia.org/wiki/Goldhttp://en.wikipedia.org/wiki/Intermetallichttp://en.wikipedia.org/wiki/Native_metalhttp://en.wikipedia.org/wiki/Antimonatehttp://en.wikipedia.org/wiki/Vanadatehttp://en.wikipedia.org/wiki/Arsenatehttp://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Apatite7/31/2019 7 Earth Materials
9/37
9 | P a g e
The Sedimentary rock is formed from the other rocks and was deposited by the waterand air. It is considered as the third in numbers among the three kinds of rocks whichcomprise about 8% of all the rocks.
This rock is exposed to the air, to the water, to the sunlight and to some acids in theenvironment. Some of this rock may contain the remains or traces of some living thingssuch as fishes, the shells, plants or mammals. These remains of the living organisms
that can be found on the sedimentary rocks are called as fossils.
The sedimentary rock is in different types. The most common of these are theconglomerate, the sandstone, the shale, the limestone and the gypsum.
The conglomerate is consists of pebbles or by pieces of gravel that are cemented
together. This type of igneous rock is usually formed in the riverbeds, in the foot of themountain or along the beaches.
The sandstone is formed when the layers of sand grains are deposited by the water or by
the wind. This will eventually packed and become cemented together.
The shale is considered as the most common type of sedimentary rock; it makes 50% ofrock that are exposed on Earth. The shale is hardened clay.
The limestone is a kind of sedimentary rock that is mostly composed of calcium
carbonate. Limestone is formed from the actions of the plants and animals in the bottomof the lakes and the oceans.
The gypsum is the kind of sedimentary rock that is formed when the hydrated calcium
sulfate in the seawater settles.
The Metamorphic rock is formed when the igneous rock or the sedimentary rock changein color in texture and on its crystal structure because of a great pressure as well astemperature. This kind of rock is considered as the second most abundant rock
comprising about 27% of all the rocks.
The most common types of the metamorphic rocks are the marble, the gneiss and thequartzite.
The marble is considered as the most widely known among the metamorphic rocks. It is
formed from the limestone but it is denser and harder. The gneiss rock is formed fromthe conglomerate or granite while the quartzite rock is formed from the sandstone; it is
heavy, hard and nonporous. It has also a grainy texture.
rock, in geology, naturally occurring and coherent aggregate of one or more minerals. Such
aggregates constitute the basic unit of which the solid Earthis comprised and typically form recognizable and
mappable volumes. Rocks are commonly divided into three major classes according to the processes that
resulted in their formation. These classes are (1) igneous rocks, which have solidified from molten material called
magma; (2) sedimentary rocks, those consisting of fragments derived from preexisting rocks or of materials
precipitated from solutions; and (3) metamorphic rocks, which have been derived from either igneous or
http://www.britannica.com/EBchecked/topic/175962/http://www.britannica.com/EBchecked/topic/175962/http://www.britannica.com/EBchecked/topic/175962/http://www.britannica.com/EBchecked/media/158662/Rocks-can-be-any-sizehttp://www.britannica.com/EBchecked/topic/175962/7/31/2019 7 Earth Materials
10/37
10 | P a g e
sedimentary rocks under conditions that caused changes in mineralogical composition, texture, and internal
structure. These three classes, in turn, are subdivided into numerous groups and types on the basis of various
factors, the most important of which are chemical, mineralogical, and textural attributes.
General considerationsRock types
Igneous rocksare those that solidify frommagma, a molten mixture of rock-
forming minerals and usually volatiles such as gases and steam. Since their
constituent minerals are crystallized from molten material, igneous rocks are formed
at high temperatures. They originate from processes deep within the Earthtypically
at depths of about 50 to 200 kilometres (30 to 120 miles)in the mid- to lower-crust
or in theupper mantle. Igneous rocks are subdivided into twocategories:intrusive(emplaced in the crust), and extrusive (extruded onto the surface
of the land or ocean bottom), in which case the cooling molten material is calledlava.
Sedimentary rocksare those that are deposited and lithified (compacted and cemented
together) at the Earths surface, with the assistance of running water, wind, ice, or
living organisms. Most are deposited from the land surface to the bottoms of lakes,
rivers, and oceans. Sedimentary rocks are generally stratifiedi.e., they have
layering. Layers may be distinguished by differences in colour, particle size, type of
cement, or internal arrangement.
Metamorphic rocksare those formed by changes in preexisting rocks under the
influence of hightemperature,pressure, and chemically active solutions. The changes
can be chemical (compositional) and physical (textural) in character. Metamorphic
rocks are often formed by processes deep within the Earth that produce
new minerals, textures, and crystal structures. Therecrystallizationthat takesplacedoes
so essentially in thesolid state, rather than by complete remelting, and can be aided
by ductile deformation and the presence ofinterstitial fluidssuch as water.
Metamorphism often produces apparent layering, or banding, because of
thesegregationof minerals into separate bands.Metamorphic processescan also occur at
the Earths surface due tometeoriteimpact events and pyrometamorphism taking
place near burningcoal seamsignited by lightning strikes.
http://www.britannica.com/EBchecked/topic/589514/http://www.britannica.com/EBchecked/topic/589514/http://www.britannica.com/EBchecked/topic/589514/http://www.britannica.com/EBchecked/topic/282318/igneous-rockhttp://www.britannica.com/EBchecked/topic/282318/igneous-rockhttp://www.britannica.com/EBchecked/topic/356805/magmahttp://www.britannica.com/EBchecked/topic/356805/magmahttp://www.britannica.com/EBchecked/topic/356805/magmahttp://www.britannica.com/EBchecked/topic/618804/upper-mantlehttp://www.britannica.com/EBchecked/topic/618804/upper-mantlehttp://www.britannica.com/EBchecked/topic/618804/upper-mantlehttp://www.britannica.com/EBchecked/topic/292149/intrusive-rockhttp://www.britannica.com/EBchecked/topic/292149/intrusive-rockhttp://www.britannica.com/EBchecked/topic/292149/intrusive-rockhttp://www.britannica.com/EBchecked/topic/332564/lavahttp://www.britannica.com/EBchecked/topic/332564/lavahttp://www.britannica.com/EBchecked/topic/332564/lavahttp://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/377777/metamorphic-rockhttp://www.britannica.com/EBchecked/topic/377777/metamorphic-rockhttp://www.britannica.com/EBchecked/topic/586581/http://www.britannica.com/EBchecked/topic/586581/http://www.britannica.com/EBchecked/topic/586581/http://www.britannica.com/EBchecked/topic/475388/http://www.britannica.com/EBchecked/topic/475388/http://www.britannica.com/EBchecked/topic/475388/http://www.britannica.com/EBchecked/topic/493872/http://www.britannica.com/EBchecked/topic/493872/http://www.britannica.com/EBchecked/topic/493872/http://www.britannica.com/EBchecked/topic/663465/http://www.britannica.com/EBchecked/topic/663465/http://www.britannica.com/EBchecked/topic/663465/http://www.britannica.com/EBchecked/topic/553257/solidhttp://www.britannica.com/EBchecked/topic/553257/solidhttp://www.britannica.com/EBchecked/topic/553257/solidhttp://www.britannica.com/EBchecked/topic/291709/interstitial-fluidhttp://www.britannica.com/EBchecked/topic/291709/interstitial-fluidhttp://www.britannica.com/EBchecked/topic/291709/interstitial-fluidhttp://www.britannica.com/EBchecked/topic/532728/http://www.britannica.com/EBchecked/topic/532728/http://www.britannica.com/EBchecked/topic/532728/http://www.britannica.com/EBchecked/topic/377802/metamorphismhttp://www.britannica.com/EBchecked/topic/377802/metamorphismhttp://www.britannica.com/EBchecked/topic/378148/http://www.britannica.com/EBchecked/topic/378148/http://www.britannica.com/EBchecked/topic/378148/http://www.britannica.com/EBchecked/topic/123005/coal-seamhttp://www.britannica.com/EBchecked/topic/123005/coal-seamhttp://www.britannica.com/EBchecked/topic/123005/coal-seamhttp://www.britannica.com/EBchecked/topic/123005/coal-seamhttp://www.britannica.com/EBchecked/topic/378148/http://www.britannica.com/EBchecked/topic/377802/metamorphismhttp://www.britannica.com/EBchecked/topic/532728/http://www.britannica.com/EBchecked/topic/291709/interstitial-fluidhttp://www.britannica.com/EBchecked/topic/553257/solidhttp://www.britannica.com/EBchecked/topic/663465/http://www.britannica.com/EBchecked/topic/493872/http://www.britannica.com/EBchecked/topic/475388/http://www.britannica.com/EBchecked/topic/586581/http://www.britannica.com/EBchecked/topic/377777/metamorphic-rockhttp://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/332564/lavahttp://www.britannica.com/EBchecked/topic/292149/intrusive-rockhttp://www.britannica.com/EBchecked/topic/618804/upper-mantlehttp://www.britannica.com/EBchecked/topic/356805/magmahttp://www.britannica.com/EBchecked/topic/282318/igneous-rockhttp://www.britannica.com/EBchecked/topic/589514/7/31/2019 7 Earth Materials
11/37
11 | P a g e
Rock cycle
Geologic materialsmineral crystals and theirhost rocktypesare
cycled through various forms. The process depends on temperature, pressure, time,
and changes in environmental conditions in theEarths crustand at its surface. The
rock cycle illustrated in Figure 1 reflects the basic relationships among
igneous, metamorphic, and sedimentary rocks.Erosionincludes weathering
(the physical and chemical breakdown of minerals) and transportation to a site of
deposition.Diagenesisis, as previously explained, the process of formingsedimentary
rockbycompactionand naturalcementationof grains, orcrystallizationfrom water or
solutions, or recrystallization. The conversion ofsedimentto rock is termedlithification.
Abundance of rock types
An estimate of the distribution of rock types in large structural units of the terrestrial
crust is given in the Table. Therelative abundanceof main rock types andminerals in the
crust is shown in the Table.
http://www.britannica.com/EBchecked/topic/229677/geologic-cyclehttp://www.britannica.com/EBchecked/topic/229677/geologic-cyclehttp://www.britannica.com/EBchecked/topic/140407/country-rockhttp://www.britannica.com/EBchecked/topic/140407/country-rockhttp://www.britannica.com/EBchecked/topic/140407/country-rockhttp://www.britannica.com/EBchecked/topic/176286/Earths-crusthttp://www.britannica.com/EBchecked/topic/176286/Earths-crusthttp://www.britannica.com/EBchecked/topic/176286/Earths-crusthttp://www.britannica.com/EBchecked/topic/191809/erosionhttp://www.britannica.com/EBchecked/topic/191809/erosionhttp://www.britannica.com/EBchecked/topic/191809/erosionhttp://www.britannica.com/EBchecked/topic/161033/diagenesishttp://www.britannica.com/EBchecked/topic/161033/diagenesishttp://www.britannica.com/EBchecked/topic/161033/diagenesishttp://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/129528/http://www.britannica.com/EBchecked/topic/129528/http://www.britannica.com/EBchecked/topic/129528/http://www.britannica.com/EBchecked/topic/101847/http://www.britannica.com/EBchecked/topic/101847/http://www.britannica.com/EBchecked/topic/101847/http://www.britannica.com/EBchecked/topic/145334/http://www.britannica.com/EBchecked/topic/145334/http://www.britannica.com/EBchecked/topic/145334/http://www.britannica.com/EBchecked/topic/532176/http://www.britannica.com/EBchecked/topic/532176/http://www.britannica.com/EBchecked/topic/532176/http://www.britannica.com/EBchecked/topic/343640/lithificationhttp://www.britannica.com/EBchecked/topic/343640/lithificationhttp://www.britannica.com/EBchecked/topic/343640/lithificationhttp://www.britannica.com/EBchecked/topic/496821/relative-abundancehttp://www.britannica.com/EBchecked/topic/496821/relative-abundancehttp://www.britannica.com/EBchecked/topic/496821/relative-abundancehttp://www.britannica.com/EBchecked/media/2460/The-rock-cyclehttp://www.britannica.com/EBchecked/media/148026/Geologic-materials-cycle-through-various-formshttp://www.britannica.com/EBchecked/media/2460/The-rock-cyclehttp://www.britannica.com/EBchecked/media/148026/Geologic-materials-cycle-through-various-formshttp://www.britannica.com/EBchecked/topic/496821/relative-abundancehttp://www.britannica.com/EBchecked/topic/343640/lithificationhttp://www.britannica.com/EBchecked/topic/532176/http://www.britannica.com/EBchecked/topic/145334/http://www.britannica.com/EBchecked/topic/101847/http://www.britannica.com/EBchecked/topic/129528/http://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/532232/sedimentary-rockhttp://www.britannica.com/EBchecked/topic/161033/diagenesishttp://www.britannica.com/EBchecked/topic/191809/erosionhttp://www.britannica.com/EBchecked/topic/176286/Earths-crusthttp://www.britannica.com/EBchecked/topic/140407/country-rockhttp://www.britannica.com/EBchecked/topic/229677/geologic-cycle7/31/2019 7 Earth Materials
12/37
12 | P a g e
7/31/2019 7 Earth Materials
13/37
13 | P a g e
Texture
The texture of a rock is the size, shape, and arrangement of the grains
(for sedimentary rocks) orcrystals(for igneous and metamorphic rocks). Also of
importance are the rocks extent ofhomogeneity(i.e., uniformity of composition
throughout) and the degree ofisotropy. The latter is the extent to which the
bulkstructure and composition are the same in all directions in the rock.
Analysis of texture can yield information about the rocks source material, conditions
and environment of deposition (for sedimentary rock) or crystallization and
recrystallization (for igneous andmetamorphic rock, respectively), and subsequentgeologic history and change.
http://www.britannica.com/EBchecked/topic/589514/texturehttp://www.britannica.com/EBchecked/topic/589514/texturehttp://www.britannica.com/EBchecked/topic/145105/crystalhttp://www.britannica.com/EBchecked/topic/145105/crystalhttp://www.britannica.com/EBchecked/topic/145105/crystalhttp://www.britannica.com/EBchecked/topic/270480/homogeneityhttp://www.britannica.com/EBchecked/topic/270480/homogeneityhttp://www.britannica.com/EBchecked/topic/270480/homogeneityhttp://www.britannica.com/EBchecked/topic/296676/isotropyhttp://www.britannica.com/EBchecked/topic/296676/isotropyhttp://www.britannica.com/EBchecked/topic/296676/isotropyhttp://www.britannica.com/EBchecked/topic/377777/metamorphic-rockhttp://www.britannica.com/EBchecked/topic/377777/metamorphic-rockhttp://www.britannica.com/EBchecked/topic/377777/metamorphic-rockhttp://www.britannica.com/EBchecked/media/159029/Rocks-have-many-different-textureshttp://www.britannica.com/EBchecked/media/159029/Rocks-have-many-different-textureshttp://www.britannica.com/EBchecked/topic/377777/metamorphic-rockhttp://www.britannica.com/EBchecked/topic/296676/isotropyhttp://www.britannica.com/EBchecked/topic/270480/homogeneityhttp://www.britannica.com/EBchecked/topic/145105/crystalhttp://www.britannica.com/EBchecked/topic/589514/texture7/31/2019 7 Earth Materials
14/37
14 | P a g e
Classification bygrainor crystal size
The common textural terms used for rock types with respect to the size of the grains
or crystals, are given in the Table. The particle-size categories are
derived from the Udden-Wentworth scale developed for sediment. For igneous
and metamorphic rocks, the terms are generally used as modifierse.g., medium-
grainedgranite.Aphaniticis a descriptive term for small crystals, andphaneriticfor larger
ones. Very coarse crystals (those larger than 3 centimetres, or 1.2 inches) are
termed pegmatitic.
For sedimentary rocks, the broad categories of sediment size are coarse (greater
than 2 millimetres, or 0.08 inch), medium (between 2 and 1/16 millimetres), and fine
(under 1/16 millimetre). The latter includessiltandclay, which both have a size
indistinguishable by the human eye and are also termeddust. Mostshales(the lithified
version of clay) contain some silt.Pyroclastic rocksare those formed from clastic (from
the Greek word for broken) material ejected from volcanoes.Blocksare fragments
broken from solid rock, whilebombsare molten when ejected.Porosity
The term rock refers to the bulk volume of the material, including the grains or
crystals as well as the contained void space. The volumetric portion of bulk rock that
is not occupied by grains, crystals, or natural cementing material is termedporosity.
That is to say, porosity is the ratio of void volume to the bulk volume (grains plus void
space). This void space consists ofporespace between grains or crystals, in addition
to crack space. In sedimentary rocks, the amount of pore space depends on the
degree of compaction of the sediment (with compaction generally increasing with
depth of burial), on thepackingarrangement and shape of grains, on the amount of
cementation, and on the degree ofsorting. Typical cements are siliceous, calcareous
or carbonate, or iron-bearing minerals.
Sorting is the tendency of sedimentary rocks to have grains that are similarly sized
i.e., to have a narrow range of sizes (see Figure 2). Poorly sorted
sediment displays a wide range of grain sizes and hence has decreased porosity.
Well-sorted indicates a grain size distribution that is fairly uniform. Depending on the
type of close-packing of the grains, porosity can be substantial. It should be noted
http://www.britannica.com/EBchecked/topic/240805/http://www.britannica.com/EBchecked/topic/240805/http://www.britannica.com/EBchecked/topic/240805/http://www.britannica.com/EBchecked/topic/241660/http://www.britannica.com/EBchecked/topic/241660/http://www.britannica.com/EBchecked/topic/29489/aphanitic-texturehttp://www.britannica.com/EBchecked/topic/29489/aphanitic-texturehttp://www.britannica.com/EBchecked/topic/29489/aphanitic-texturehttp://www.britannica.com/EBchecked/topic/455055/phaneritic-texturehttp://www.britannica.com/EBchecked/topic/455055/phaneritic-texturehttp://www.britannica.com/EBchecked/topic/455055/phaneritic-texturehttp://www.britannica.com/EBchecked/topic/544666/silthttp://www.britannica.com/EBchecked/topic/544666/silthttp://www.britannica.com/EBchecked/topic/544666/silthttp://www.britannica.com/EBchecked/topic/120654/clayhttp://www.britannica.com/EBchecked/topic/120654/clayhttp://www.britannica.com/EBchecked/topic/120654/clayhttp://www.britannica.com/EBchecked/topic/174452/http://www.britannica.com/EBchecked/topic/174452/http://www.britannica.com/EBchecked/topic/174452/http://www.britannica.com/EBchecked/topic/538082/shalehttp://www.britannica.com/EBchecked/topic/538082/shalehttp://www.britannica.com/EBchecked/topic/538082/shalehttp://www.britannica.com/EBchecked/topic/484950/pyroclastic-rockhttp://www.britannica.com/EBchecked/topic/484950/pyroclastic-rockhttp://www.britannica.com/EBchecked/topic/484950/pyroclastic-rockhttp://www.britannica.com/EBchecked/topic/632020/volcanic-blockhttp://www.britannica.com/EBchecked/topic/632020/volcanic-blockhttp://www.britannica.com/EBchecked/topic/632020/volcanic-blockhttp://www.britannica.com/EBchecked/topic/72485/bombhttp://www.britannica.com/EBchecked/topic/72485/bombhttp://www.britannica.com/EBchecked/topic/72485/bombhttp://www.britannica.com/EBchecked/topic/470674/porosityhttp://www.britannica.com/EBchecked/topic/470674/porosityhttp://www.britannica.com/EBchecked/topic/470674/http://www.britannica.com/EBchecked/topic/470674/http://www.britannica.com/EBchecked/topic/470674/http://www.britannica.com/EBchecked/topic/470582/porehttp://www.britannica.com/EBchecked/topic/470582/porehttp://www.britannica.com/EBchecked/topic/470582/porehttp://www.britannica.com/EBchecked/topic/437906/http://www.britannica.com/EBchecked/topic/437906/http://www.britannica.com/EBchecked/topic/437906/http://www.britannica.com/EBchecked/topic/554990/sortinghttp://www.britannica.com/EBchecked/topic/554990/sortinghttp://www.britannica.com/EBchecked/topic/554990/sortinghttp://www.britannica.com/EBchecked/media/2461/Sortinghttp://www.britannica.com/EBchecked/media/61500/http://www.britannica.com/EBchecked/media/2461/Sortinghttp://www.britannica.com/EBchecked/media/61500/http://www.britannica.com/EBchecked/topic/554990/sortinghttp://www.britannica.com/EBchecked/topic/437906/http://www.britannica.com/EBchecked/topic/470582/porehttp://www.britannica.com/EBchecked/topic/470674/http://www.britannica.com/EBchecked/topic/470674/porosityhttp://www.britannica.com/EBchecked/topic/72485/bombhttp://www.britannica.com/EBchecked/topic/632020/volcanic-blockhttp://www.britannica.com/EBchecked/topic/484950/pyroclastic-rockhttp://www.britannica.com/EBchecked/topic/538082/shalehttp://www.britannica.com/EBchecked/topic/174452/http://www.britannica.com/EBchecked/topic/120654/clayhttp://www.britannica.com/EBchecked/topic/544666/silthttp://www.britannica.com/EBchecked/topic/455055/phaneritic-texturehttp://www.britannica.com/EBchecked/topic/29489/aphanitic-texturehttp://www.britannica.com/EBchecked/topic/241660/http://www.britannica.com/EBchecked/topic/240805/7/31/2019 7 Earth Materials
15/37
15 | P a g e
that in engineering usagee.g., geotechnical orcivil engineeringthe terminology is
phrased oppositely and is referred to asgrading. A well-graded sediment is a
(geologically) poorly sorted one, and a poorly graded sediment is a well-sorted one.
Total porosity encompasses all the void space, including those pores that areinterconnected to the surface of the sample as well as those that are sealed off by
natural cement or other obstructions. Thus the total porosity (T) is
where VolG is the volume of grains (and cement, if any) and VolB is the total bulk
volume. Alternatively, one can calculate T from the measured densities of the bulk
rock and of the (mono)mineralic constituent. Thus,
where Bis the density of the bulk rock and G is the density of the grains
(i.e., themineral, if the composition is monomineralogic and homogeneous). For
example, if asandstonehas a B of 2.38 grams per cubic centimetre (g/cm3) and is
composed of quartz (SiO2) grains having G of 2.65 g/cm3, the total porosity is
Apparent (effective, or net) porosity is the proportion of void space that excludes
the sealed-off pores. It thus measures the pore volume that is effectively
interconnected and accessible to the surface of the sample, which is important when
considering the storage and movement of subsurface fluids such as petroleum,
groundwater, or contaminated fluids.
Physical properties
Physical properties of rocks are of interest and utility in many fields of work, includinggeology, petrophysics, geophysics,materials science, geochemistry, andgeotechnical
engineering. The scale of investigation ranges from the molecular and crystalline up to
terrestrial studies of the Earth and other planetary bodies.Geologistsare interested in
the radioactive age dating of rocks to reconstruct the origin of mineral
deposits;seismologistsformulate prospective earthquake predictions using
premonitory physical or chemical changes;crystallographersstudy the synthesis of
minerals with special optical or physical properties;
explorationgeophysicistsinvestigate the variation of physical properties of subsurface
http://www.britannica.com/EBchecked/topic/119227/civil-engineeringhttp://www.britannica.com/EBchecked/topic/119227/civil-engineeringhttp://www.britannica.com/EBchecked/topic/240587/http://www.britannica.com/EBchecked/topic/240587/http://www.britannica.com/EBchecked/topic/240587/http://www.britannica.com/EBchecked/topic/383675/http://www.britannica.com/EBchecked/topic/383675/http://www.britannica.com/EBchecked/topic/383675/http://www.britannica.com/EBchecked/topic/522190/http://www.britannica.com/EBchecked/topic/522190/http://www.britannica.com/EBchecked/topic/369081/materials-sciencehttp://www.britannica.com/EBchecked/topic/369081/materials-sciencehttp://www.britannica.com/EBchecked/topic/369081/materials-sciencehttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/229724/geologyhttp://www.britannica.com/EBchecked/topic/229724/geologyhttp://www.britannica.com/EBchecked/topic/229724/geologyhttp://www.britannica.com/EBchecked/topic/532955/seismologyhttp://www.britannica.com/EBchecked/topic/532955/seismologyhttp://www.britannica.com/EBchecked/topic/532955/seismologyhttp://www.britannica.com/EBchecked/topic/145364/crystallographyhttp://www.britannica.com/EBchecked/topic/145364/crystallographyhttp://www.britannica.com/EBchecked/topic/145364/crystallographyhttp://www.britannica.com/EBchecked/topic/229918/geophysicshttp://www.britannica.com/EBchecked/topic/229918/geophysicshttp://www.britannica.com/EBchecked/topic/229918/geophysicshttp://www.britannica.com/EBchecked/topic/229918/geophysicshttp://www.britannica.com/EBchecked/topic/145364/crystallographyhttp://www.britannica.com/EBchecked/topic/532955/seismologyhttp://www.britannica.com/EBchecked/topic/229724/geologyhttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/369081/materials-sciencehttp://www.britannica.com/EBchecked/topic/522190/http://www.britannica.com/EBchecked/topic/383675/http://www.britannica.com/EBchecked/topic/240587/http://www.britannica.com/EBchecked/topic/119227/civil-engineering7/31/2019 7 Earth Materials
16/37
16 | P a g e
rocks to make possible detection of natural resources such as oil and gas,geothermal
energy, and ores of metals;geotechnical engineersexamine the nature and behaviour of
the materials on, in, or of which such structures as buildings, dams, tunnels, bridges,
and underground storage vaults are to be constructed;solid-state physicistsstudy themagnetic, electrical, and mechanical properties of materials for electronic devices,
computer components, or high-performance ceramics; and
petroleumreservoirengineers analyze the response measured on well logs or in the
processes of deep drilling at elevated temperature and pressure.
Since rocks are aggregates of mineral grains or crystals, their properties are
determined in large part by the properties of their various constituent minerals. In a
rock these general properties are determined by averaging the relative properties
and sometimes orientations of the various grains or crystals. As a result, some
properties that are anisotropic (i.e., differ with direction) on a submicroscopic or
crystalline scale are fairly isotropic for a large bulk volume of the rock. Many
properties are also dependent on grain or crystal size, shape, and packing
arrangement, the amount and distribution of void space, the presence of natural
cements in sedimentary rocks, the temperature and pressure, and the type and
amount of contained fluids (e.g., water, petroleum, gases). Because many rocks
exhibit a considerable range in these factors, the assignment of representative
values for a particular property is often done using a statistical variation.
Some properties can vary considerably, depending on whether measured in situ (in
place in the subsurface) or in the laboratory under simulated conditions.
Electricalresistivity, for example, is highly dependent on the fluid content of the rock in
situ and the temperature condition at the particular depth.Density
Density varies significantly among different rock types because of differences inmineralogy and porosity. Knowledge of the distribution of underground rock densities
can assist in interpreting subsurface geologic structure and rock type.
In strict usage, density is defined as the mass of a substance per unit volume;
however, in common usage, it is taken to be theweightin air of a unit volume of a
sample at a specific temperature. Weight is the force that gravitation exerts on a
body (and thus varies with location), whereasmass(a measure of thematterin a body)
is a fundamental property and is constant regardless of location. In routine density
measurements of rocks, the sample weights are considered to be equivalent to their
http://www.britannica.com/EBchecked/topic/230403/geothermal-energyhttp://www.britannica.com/EBchecked/topic/230403/geothermal-energyhttp://www.britannica.com/EBchecked/topic/230403/geothermal-energyhttp://www.britannica.com/EBchecked/topic/230403/geothermal-energyhttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/1240456/solid-state-physicshttp://www.britannica.com/EBchecked/topic/1240456/solid-state-physicshttp://www.britannica.com/EBchecked/topic/1240456/solid-state-physicshttp://www.britannica.com/EBchecked/topic/499110/reservoir-engineeringhttp://www.britannica.com/EBchecked/topic/499110/reservoir-engineeringhttp://www.britannica.com/EBchecked/topic/499254/resistancehttp://www.britannica.com/EBchecked/topic/499254/resistancehttp://www.britannica.com/EBchecked/topic/499254/resistancehttp://www.britannica.com/EBchecked/topic/157956/densityhttp://www.britannica.com/EBchecked/topic/157956/densityhttp://www.britannica.com/EBchecked/topic/638947/weighthttp://www.britannica.com/EBchecked/topic/638947/weighthttp://www.britannica.com/EBchecked/topic/368127/masshttp://www.britannica.com/EBchecked/topic/368127/masshttp://www.britannica.com/EBchecked/topic/368127/masshttp://www.britannica.com/EBchecked/topic/369668/http://www.britannica.com/EBchecked/topic/369668/http://www.britannica.com/EBchecked/topic/369668/http://www.britannica.com/EBchecked/topic/369668/http://www.britannica.com/EBchecked/topic/368127/masshttp://www.britannica.com/EBchecked/topic/638947/weighthttp://www.britannica.com/EBchecked/topic/157956/densityhttp://www.britannica.com/EBchecked/topic/499254/resistancehttp://www.britannica.com/EBchecked/topic/499110/reservoir-engineeringhttp://www.britannica.com/EBchecked/topic/1240456/solid-state-physicshttp://www.britannica.com/EBchecked/topic/187561/engineering-geologyhttp://www.britannica.com/EBchecked/topic/230403/geothermal-energyhttp://www.britannica.com/EBchecked/topic/230403/geothermal-energy7/31/2019 7 Earth Materials
17/37
17 | P a g e
masses, because the discrepancy between weight and mass would result in less
error on the computed density than the experimental errors introduced in the
measurement of volume. Thus, density is often determined using weight rather than
mass. Density should properly be reported in kilograms per cubic metre (kg/m3
), butis still often given in grams per cubic centimetre (g/cm3).
Another property closely related to density isspecific gravity. It is defined, as noted
above, as the ratio of the weight or mass in air of a unit volume of material at a
stated temperature to the weight or mass in air of a unit volume of distilled water at
the same temperature. Specificgravityis dimensionless (i.e., has no units).
Thebulk densityof a rock is B = WG/VB, where WG is the weight of grains (sedimentary
rocks) or crystals (igneous and metamorphic rocks) and natural cements, if any,
and VB is the total volume of the grains or crystals plus the void (pore) space. The
density can be dry if the pore space is empty, or it can be saturated if the pores are
filled with fluid (e.g., water), which is more typical of the subsurface (in situ) situation.
If there is pore fluid present,
where Wfl is the weight of pore fluid. In terms of total porosity, saturated density is
and thus
where fl is the density of the pore fluid. Density measurements for a given specimen
involve the determination of any two of the following quantities: pore volume, bulk
volume, or grain volume, along with the weight.
A useful way to assess the density of rocks is to make a histogram plot of the
statistical range of a set of data. The representative value and its variation can be
expressed as follows: (1) mean, the average value, (2) mode, the most common
value (i.e., the peak of the distribution curve), (3) median, the value of the middle
sample of thedata set(i.e., the value at which half of the samples are below and half
are above), and (4)standard deviation, a statistical measure of the spread of the data
(plus and minus one standard deviation from the mean value includes about two-
thirds of the data).
A compilation of dry bulk densities for various rock types found in the upper crust of
the Earth is listed in the Table. A histogram plot of these data, giving the percent of
http://www.britannica.com/EBchecked/topic/558700/specific-gravityhttp://www.britannica.com/EBchecked/topic/558700/specific-gravityhttp://www.britannica.com/EBchecked/topic/558700/specific-gravityhttp://www.britannica.com/EBchecked/topic/242523/http://www.britannica.com/EBchecked/topic/242523/http://www.britannica.com/EBchecked/topic/242523/http://www.britannica.com/EBchecked/topic/84262/bulk-densityhttp://www.britannica.com/EBchecked/topic/84262/bulk-densityhttp://www.britannica.com/EBchecked/topic/84262/bulk-densityhttp://www.britannica.com/EBchecked/topic/692219/data-sethttp://www.britannica.com/EBchecked/topic/692219/data-sethttp://www.britannica.com/EBchecked/topic/692219/data-sethttp://www.britannica.com/EBchecked/topic/562938/standard-deviationhttp://www.britannica.com/EBchecked/topic/562938/standard-deviationhttp://www.britannica.com/EBchecked/topic/562938/standard-deviationhttp://www.britannica.com/EBchecked/topic/562938/standard-deviationhttp://www.britannica.com/EBchecked/topic/692219/data-sethttp://www.britannica.com/EBchecked/topic/84262/bulk-densityhttp://www.britannica.com/EBchecked/topic/242523/http://www.britannica.com/EBchecked/topic/558700/specific-gravity7/31/2019 7 Earth Materials
18/37
18 | P a g e
the samples as a function of density is shown in Figure 3. The
parameters given include (1) sample division, the range of density in one data
columne.g., 0.036 g/cm3 for Figure 3, (2) number of samples, and (3) standard
deviation. The small inset plot is the percentage of samples (on the vertical axis) that
lie within the interval of the mode -x to the mode +x, wherex is the horizontal
axis.
Dry bulk densities for various rock types
rock type number ofsamples mean (gramsper cubic cm) standarddeviation mode (gramsper cubic cm) median (gramsper cubic cm)
all rocks 1,647 2.73 0.26 2.65 2.86
andesite 197 2.65 0.13 2.58 2.66
basalt 323 2.74 0.47 2.88 2.87
diorite 68 2.86 0.12 2.89 2.87
dolerite
(diabase)224 2.89 0.13 2.96 2.90
gabbro 98 2.95 0.14 2.99 2.97
granite 334 2.66 0.06 2.66 2.66
quartz
porphyry
76 2.62 0.06 2.60 2.62
rhyolite 94 2.51 0.13 2.60 2.49
syenite 93 2.70 0.10 2.67 2.68
trachyte 71 2.57 0.10 2.62 2.57
sandstone 107 2.22 0.23 2.22 2.22
Source: After data from H.S. Washington (1917) and R.J. Piersol, L.E. Workman, and M.C. Watson (1940) as compiled
http://www.britannica.com/EBchecked/media/2450/Dry-bulk-densities-for-all-rocks-given-in-Table-337/31/2019 7 Earth Materials
19/37
19 | P a g e
by Gary R. Olhoeft and Gordon R. Johnson in Robert S. Carmichael, ed., Handbook of Physical Properties of Rocks, vol. III,
CRC Press, Inc. (1984).
Question: What Is the Most Abundant Element?
Answer: The most abundant element in the universe is hydrogen, which makes up about 3/4 of all matter! Helium makes upmost of the remaining 25%. Oxygen is the third most abundant element in the universe. All of the other elements are
relatively rare.
The chemical composition of the earth is quite a bit different from that of the universe. The most abundant element in the
earth's crust is oxygen, making up 46.6% of the earth's mass. Silicon is the second most abundant element (27.7%), followed
by aluminum (8.1%), iron (5.0%), calcium (3.6%), sodium (2.8%), potassium (2.6%). and magnesium (2.1%). These eight
elements account for approximately 98.5% of the total mass of the earth's crust. Of course, the earth's crust is only the outer
portion of the earth. Future research will tell us about the composition of the mantle and core.
This table shows the chemical composition or abundance of chemical compounds in the Earth's crust. As you can see, the
most comm
Top Related