What is a Mineral? SWBAT define mineral; describe how minerals form; identify the most common elements in earth’s crust.

What do minerals play an important part in? Earth’s crust is composed of over 3000 minerals. They play an important role in forming rocks and shaping Earth’s crust. Some have played an important role in shaping civilization. –Iron - tools –Calcite – pyramids, Parthenon –Gold/silver – monetary value

What is a mineral? Mineral –A naturally occurring, inorganic solid with a specific chemical composition and a definite crystalline structure.

Mineral Characteristics: Naturally occurring and inorganic –Formed by natural processes –They aren’t alive and never were Salt is a mineral Sugar is harvested from plants, and is not a mineral

Mineral Characteristics:  Solids with specific compositions –Have definite shape and volume No gas or liquid can be a mineral –Each has a unique chemical composition Some are composed of pure elements –Sulfur –Copper Some are compounds –Quartz 2 oxygen, 1 silicon SiO 2

Mineral Characteristics:  Crystalline structure –The atoms in minerals are arranged in regular geometric patterns that repeat Crystal –A solid in which the atoms are arranged in a repeating pattern Well defined crystals need a lot of space to form

Minerals from Magma Magma –Molten material found beneath Earth’s surface –The type and amount of elements present determine which minerals will form –The rate at which magma cools determines the size of the crystals The slower the cooling time, the larger the crystals

Minerals from Solutions Supersaturation –When water cannot dissolve any more of a solid –Crystals begin to precipitate, or drop out of the solution If the liquid evaporates the elements left behind begin to arrange into crystals

Mineral Groups 30 common minerals referred to as rock forming minerals, because they make up most of the rocks on earth surface –Silicates Contain oxygen and silicon Make up about 96% of minerals found in the crust Their tetrahedron shape allows for various types of structure formation –Carbonates Composed of one or more metallic elements with a carbonate compound (carbon and oxygen) –Oxides Compounds of oxygen and a metal

Mineral Groups Sulfides –Compounds of sulfur and one or more elements Sulfates –Composed of elements with the sulfate compound SO 4 Halides –Made up of chlorine or fluoride as well as calcium, sodium, or potassium Native Element –Made up of one element only