Identify That Rock for Beginners Shelby Raymond Rev7!18!09

8/9/2019 Identify That Rock for Beginners Shelby Raymond Rev7!18!09

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Identify that Rock: a Basic Tutorial for Beginners Page: 1

Rev. 7-18-09 All Rights Reserved Copyright 2008 Shelby Raymond, Skeena Storm Stones

Agates & jaspers from HaidaGwaii (a.k.a. The Queen

Charlotte Islands, BritishColumbia, Canada)

River stones from on the shore of the Skeena River nearTerrace, British Columbia, Canada

Identify That Rock!: A

Basic Tutorial for Beginners

Created by Shelby Raymond, Skeena Storm Stones

This lesson shows how to identify stones anddetermine whether or not they are appropriatefor use in jewelry and how you will prepare them.

MATERIALS and TOOLS :

Random selection of stones

Rock ID Kit:

One piece of shatter proof glass (about 1-2inches in length, with no sharp edges, at

least 1/8 of an inch thick)

1-ceramic, unglazed white tile (2x2 square)1-ceramic, unglazed black tile (2x2 square)Jewelers Loupe (usually 10x magnification)

Steel nail or small fragment of steelVinegar in a small vialSmall eyedropperContainer to hold all of the above

Notepad to record your findingsPaper or cloth towels to wipe up spills

Container to hold your rock samples while

you are working with them

Table cover I use pieces of felt to cover mytable. I strongly suggest this so you can

avoid scratching your furniture.

Legal Stuff: By using and viewing the content of thistutorial, you agree not to distribute, lend or copy any

portion of this document; to not mass produce thisdocument and to hold Skeena Storm Stones and

Shelby Raymond and Skeena Rocks! free of any and all

claims. This content is provided AS IS. If you wish touse this in a classroom setting, please contact theauthor for written permission prior to use.*Children should always be supervised by a responsibleadult.

Whew! Got it all? Agree to the terms? Then please,read on, be safe and have FUN!

If you have questions, please do not hesitate to contactme.

Fibrous Malachite Wulfenite Molybdenum

GrossularGarnet

Gypsum Crystals

2 variety of Topaz

Vanadinite

Apache Tear inPerlite

Hemimorphite inScoria

Tourmaline Crystals:Red, Black & Green

Flourite

Variety of Igneous Rocks

Stilbite crystals


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(clockwise from top center): (1)gabbro, (2)diorite,(3)scoria, (4)basalt, (5)pumice, (6)granite, (7)tuff, (8)obsidian

STEP 1: ROCK TALK

Well start with a couple of definitions so that

we are all talking the same language!

IgneousIgneous rocks are formed when melted

rock, from deep inside the earth or a

volcano, makes it way to the surfaceand then cools quickly. e.g. granite

and obsidian

2 Types of Igneous Rocks:a. Intrusive = magma that cools

beneath the surface (i.e. granite)b. Extrusive = magma that cools

above the surface, i.e. lava, basalt

(clockwise from top, center) (9)oil shale, (10)breccia,(11)shale, (12)conglomerate, (13)limestone, (14)arkose,(15)lignite coal, (16)fossiliferous limestone, (17)brachiopod limestone,(18) travertine, (19)sandstone,(20)calcareous tufa

SedimentarySedimentary rocks are formed when

stuff piles up like stones, shells,plant material, etc. As these itemspile up on top of one another, they put

pressure on the bottom layer, whichcauses the items to stick together eventually forming a solid rock. Quite

frequently youll be able to see the

layering effect.

Sedimentary rocks can be used inmaking jewelry, however, most are

very soft and need to be stabilized orplaced in epoxy to protect them from

every day bumps and even weather!

You will find fossil evidence in

sedimentary rocks more frequentlythan the other two types. This is

because the heat involved in the

creation of igneous stones usuallydestroys the object. Heat and pressure

frequently destroy potential fossil

objects during the creation ofmetamorphic stones.

7

6

5

2

3

4

1

8

9

10

11

19

1820

1316

14

17

12

15

3 Main Categories of Rock:1. Igneous2.

Sedimentary

3. Metamorphic


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(Clockwise from top, center): (21)hornfels, (22)gneiss,(23) marble, (24)phyllite, (25) quartzite, (26) slate, (27)

anthracite coal, (28) phyllite, (29) amphibolite

MetamorphicA metamorphic rock is created when other

rocks, igneous or sedimentary, are heated

or squeezed. This usually happens inside

the earth and the heat and squeezingmakes the rocks form into something that

can be completely different. You can see

this effect in some stones or even on thesides of some mountains when there is a

folding effect. e.g. slate, gneiss

The crystals in metamorphic rocks are still

somewhat easy to see, though they aremore finely grained than their

sedimentary counterparts.i.e. limestone marble,

clusters of quartz quartzite

To the left are pictures of some of the

commonly found metamorphic rocks.

Mica var. Biotite Perfect Cleavage

Snowflake obsidian conchoidal fracture

Breaking Up is Hard to Do: Cleavage &Fracture

Another identity helper is to find out the

shapes formed on a rocks surface when

that rock breaks.

To the left is a picture of Mica. This is

commonly found, especially in granitic

rocks. Mica breaks into layers of thinsheets. Dark Mica, like you see here, is

dark because it contains iron &

magnesium. You canuse mica in jewelry,but it would be best supported in a gel or

epoxy because it is extremely fragile. As a

component in another stone it doesntusually pose problems, but the stone may

be more likely to fracture in mica planes.

2526

24

2329

22

21

27

28

Common Types of Fracture/Cleavage:

Perfect Cleavage as in mica, thinsheets along a plane

Conchoidal fracture-the breakcurves, kind of like a seashell or bowlshape could fit into the curve of thefracture.


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Identify that Rock: a Basic Tutorial

Rev. 7-18-09

Amethyst is a type of Quartz (both piconsidered a semi-precious stone.

To the left is a flcrystals are octasides). Most min

crystal formationidentify stones.

MOHS Scale of Hardness

1. Talc2. Gypsum

3. Calcite4.

Flourite

5. Apatite (turquoise, lapi6. Orthoclase feldspar (ep

labradorite)

7. Quartz (amethyst, ave8. Topaz (spinel, zirconia)

9. Corundum (ruby, sapp

10.Diamond

Quickie MOHS

2.5 = fingernail 5.

3.5 = penny 6.

Grossular garnet, var. Hemetamorphosed impure lime

garne

for Beginners

ll Rights Reserved Copyright 2008 Shelby

tured above) and is

orite crystal; fluoriteedral (they have 8rals have a typical

and this can help you

Crystal:A crystal is the

on as it grows.seen crystals su

amethyst. Theusually found inroom to grow a search on the

selenite gypsuNaica mine, Ca

Chihuahua City,

amazed!

Gem:

Its kind of challa gem is. Usuallstones, such as

although opalsdefinition! Gemformed in igneo

rock. They are

in fact, the ravaluable it tendusually brighter

impurities than

cousins.

Mineral:

Minerals are theuniverse. Most

minerals. Eachscientifically de

and the atoms

arranged, in a v

s lazuli)idote,

turine)

ire)

5 = pocket knife

5 = steel file

MOHS Scale of Hard

The MOHS Scale of Ha

easy guide to help yourock is and it also aids

rock. The softest stonewith diamond being th

10.

Harder minerals (highe

scale) will scratch soft

smaller numbers). i.e.orthoclase, apatite, fluand talc, but it will not

corundum or diamond!

sonite instone matrix

(gem)

Page: 4

Raymond, Skeena Storm Stones

orm a mineral takes

ou have probablych as rose quartz or

iggest crystals areareas where there iscrevices and caves. Dointernet for the giant

crystals found in thee of Swords, south of

Mexico you WILL be

enging to define whaty gems are the hardestdiamonds and ruby -

ive lie to thats are also usuallyus or metamorphic

also usually quite rare

er the stone, the moreto be. Gems are

and contain fewer

their semi-precious

building blocks of theocks are made up of

ineral has a clearly,ined chemical content

re put together,

ery specific way.

ess

dness is a quick and

figure out how hard ayou in identifying the

is Talc at number 1,hardest at number

r numbers on the

r ones (the ones with

quartz will scratchrite, calcite, gypsumscratch topaz,


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This is a great bookthat was written by alocal geologist. With

this knowledge inhand, combined withinformation on whatformations are likely

to contain specific

stones, my rock huntsare usually

successful.

Map of world showing the distribution of major deposits plotted on digital

elevation model with draped geology from Geological Survey of Canada,

Open File 2915d, 1995.Data from the synthesis of ore deposits. Data

plotted and diagrams prepared by W.D. Goodfellow.

The Skeen River, Terrace, British Columbia, Canada

STEP 2: KNOW YOUR PLACE

Learn about the area in which you live, or

places you can easily visit. Usually itspossible to find a rockhound group,lapidary or mineral society. They are

wonderful sources of information.

Government websites also haveinformation on the geography and

geology of most regions. Its easy to

download maps or brochures that detailwhat kinds of minerals and rocks may benearby.

Take a class in geography, geology or

rockhounding. Not only will you meetpeople with similar interests, but you mayalso learn of some new collecting sites!

STEP 3: MIND YOUR MANNERS

Whenever you are out looking for rocks,have a rockhounding buddy with you and

make sure others know where you aregoing and approximately when you will

return.

Always get permission before entering

private land. When in doubt, check withlocal authorities.

Be careful. Take a first aid kit and knowthe local numbers for emergencyassistance. Avoid active slide areas no

matter how great the find! Remember

that caves can be dangerous only enterwith a trained spelunker.

Know the type of rocks and minerals you

will encounter beforehand. You want toavoid handling dangerous rocks and

minerals. Galena (grey and very heavy)and sulfur (usually BRIGHT yellow) shouldonly be handled with gloved hands.

Finally, leave the places you rockhound asyou found them. Pick up litter and debris;fill holes, respect landowners and others

who use the area.


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zircon

4. WHERE IN THE MOHS IS IT?

By placing a rock within the MOHS scale, you

are able to estimate the hardness of that

rock. This can be helpful in identifying astone.

When testing for MOHS, you dont need toscratch with all of your strength. Using

normal pressure, like what you use when you

are writing with a pencil, scrape the testingstone or tool across your rock.

Repeat this until your stone is scratched. If

your stone is special, dont use these tests, ordo them in an area you wont notice.

Fibrous malachite

5. LOOKS DO COUNT

Colour is extremely important in the

identification of many rocks. Once you haveseen the green of malachite you will always

remember it.

The appearance, or luster, of rocks is also

helpful in their identification. Some will looksome will look dull like chalk (slate has a

chalk dullness), glassy like a drinkingglass (think of quartz or obsidian); greasy

(graphite has a greasy feel); silky like silk(asbestos types look silky).

The mineral sample above is galena. This is a

toxic mineral you should avoid handling with

bare hands. It, and lead, are noticeablyheavier than most rocks.

6. IT AINT HEAVY ITS JUST TALC

When you look in rock identification books,

they usually provide the specific gravity (SG)

of a rock or mineral. This is basically a

comparison of the mineral or rock compared tothe weight of an equal volume of water. Water

has a SG of 1.

Rocks that seem heavy for their size usually

have a high density. The density of a stonegenerally refers to how tightly packed thecrystals are. i.e. Galena has an SG of~7.4-

7.6 and is quite dense, whereas sulfur weighs

in at ~2-2.1 and isnt nearly as dense as the

galena.


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Common Streak Colours

Limonite = Yellow-brownHematite = Red-brown

Gold = yellowGalena = greyGraphite = blackPyrite = black

Magnetite = black

Chalcopyrite = black

Below are a couple of examples where knowingthe streak colour of stones can be quite useful.

The colour streak for gold is yellow and Fools

Gold (Pyrite) has a red streak!

Hematite (a popular jewelry making stone) has

a read streak, while galena (a toxic stone withsimilar outward features) has a grey streak.

7. STREAKING IS ALLOWED

When it comes to rock & mineral identification

streaking is allowed! In fact, it is

encouraged! This is where the ceramic streakplates in your kit will come in handy.

To find out what colour streak your rock has,you will scratch it across both plates the

white and the black unglazed ceramic.

Sometimes youll be surprised, as the streakleft by a stone may be completely differentthan the colour of its actual physical

appearance! Minerals harder than the plate

will not leave a streak.

It is important to note that most silicates(most of the stones we use in jewelry fall intothe silicate class) have a white streak and thismay not help identify them.

Rocks that contain calcium carbonate: Calcite (it IS calcium carbonate!) Limestone

Marble (it is compressed limestone)

Carbonatite Mexican Onyx

Iceland Spar

8. POP, POP, FIZZ, FIZZNext we will play with the vinegar and the

nail. This tiny experiment can help you findout if there is calcite (calcium carbonate)

present in your rock. Calcite is one of the

most common minerals on earth - ~4% of the

earths crust (by weight).

Holding your rock firmly in your hand, scratchthe surface with either a pocket knife or thenail in your ID kit. If you cant scratch up alittle bit of shavings, you definitely dont

have a rock that contains calcite.

Now, drop one drop of vinegar onto the pile of

shavings. If it fizzes, calcite is present. If itdoesnt, you probably dont have calcite in

your rock.

Some folks use Muriatic (hydrochloric) acid in10% dilution for this test. Because Muriaticacid can be extremely dangerous to handle,

its not something I suggest. Handling

Muriatic acid requires special training andhazard containment procedures.

Calcite can be the glue in:

Sandstone

Slate


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The rock above is the one well identify in this tutorial.

9. WHAT IS IT?Take out your first rock and give it a good look-

over. You might already have a good idea if you

are using a rockhound guide or map of deposits.

Can you tell if it is Igneous, Sedimentary orMetamorphic?

My sample at left is Igneous it looks

like it cooled quickly because I dont see

any specific crystal formations.

What kind of fracture or cleavage does it have?

The fractures are conchoidal. With my

jewelers loupe I can see little dishesor bowl shapes.

Where in the MOHS is this rock? Now well use

the MOHS scale to test my rock. Will #1 on the

MOHS scale scratch it?No

In fact, this stone isnt scratched until

we get to #8 on the MOHS scale. I tested

it with zircon and it does scratch mystone. I also dragged my stone across

the glass plate, just a little pressure is

necessary. It scratched the plate. Now I

know my stone is softer than #9.

I tried scratching it with my nail and couldnt get

any shavings.

This tells me two things: 1. I dont have

calcium carbonate present in my rockand my rock is harder than the knife so

the MOH is greater than~5.5.

I know by observation that my stone is pink in

appearance, as well as translucent and glassy. I

also know that the area is known for quartz;specifically rose quartz is frequently found. I

looked in my mineral book and sure enough,

everything matches up to rose quartz.

With all of the information I now have, I

know that my stone is rose quartz.

THANK YOU!

I hope this tutorial will help you identify some ofthe basic stones in your world. Remember, evenexperts have times when they cant identify a

rock specimen and need have it examined undera special microscope or have a chemical analysis.

The best way to learn about

rocks is to meet with other

enthusiasts and explore asmany different stones as

possible. One of the best

ways I learn about stones isthrough The Mineral of the

Month Club.

I wish you a future filled

with fascinating andbeautiful rocks and

minerals! In my humbleopinion, even a plain old basalt river rock is

gorgeous enough to be used in making jewelry;

in fact it is one of my favourites!

For comments or

questions, please go to

JewelryLessons.com

Please do not distributeor copy.

Copyrights 2008, Shelby Raymond, Skeena StormStones, http://skeenastormstones.com

All photos contained within this tutorial are theexclusive property of Shelby Raymond.

Map photo on page 5 is the property of theGovernment of Canada, do not use without their

express permission.


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SUGGESTED REFERENCES

A Field Guide to the Identification of Pebbles. Eileen Van der Flier-Keller. Harbour

Publishing.2006. ISBN-10:1-55017-395-2 (This is an AWESOME little reference for identifying river

rocks and regular stones!)

Rocks & Minerals. DK Publishing.2003. ISBN-13: 978-0-7894-9587-7

Guide to Minerals, Rocks & Fossils. A.C. Bishop, A.R. Woolley, W.R. Hamilton. Firefly Books.ISBN: 1-55407-054-6

National Audobon Society - First Field Guide: Rocks and Minerals. Edward Ricciuti, MargaretW. Carruthers. Scholastic Inc. 1998. ISBN: 0-590-0584-8

Mineral of the Month Club, http://mineralofthemonthclub.org (Please tell them Shelby Raymondreferred you! Thanks.)

The Mineral and Locality Database, http://mindat.org

Amethyst Galleries' Mineral Gallery, http://mineral.galleries.com/

Identify That Rock for Beginners Shelby Raymond Rev7!18!09

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