MINERALS

MINERALS Minerals are naturally occurring

substances. They are often solid with a definite

chemical composition. They have an orderly arrangement of

atoms, ions, and molecules that are in a crystalline structure.

Most are inorganic.

MINERALS Minerals can be formed in one of

following ways:a. Solidification from a meltb. Precipitation from a water solutionc. Diffusion through a solidd. Metabolism of organismse. Precipitation from a gas

MINERALS There are close to 4,000 known types of

minerals. Each has a name with distinctive

physical properties. These properties include: color, streak,

luster, hardness, specific gravity, crystal habit, and cleavage.

MINERALS These physical properties reflect the

mineral’s chemical composition and crystal structure.

These physical properties can be used to identify minerals.

MINERALS Minerals can be grouped into classes

according to their chemical composition for identification.

These classes include: silicates, oxides, sulfides, sulfates, halides, carbonates, and native metals.

MINERALS Silicate minerals are the most common

on Earth. A silicon-oxygen tetrahedron, which is a

silicon atom surrounded by four oxygen atoms, is the building block of silicate minerals.

Groups of silicates are distinguished from one another by how the silicon-oxygen tetrahedra that constitute them are linked.

MINERALS Gemstones are minerals known for

beauty and how rare they are. Facets can be cut into them gems so

they can be used in jewelry. Faceting is done by grinding and

polishing the gemstone on a faceting machine.