What is a Mineral?What is a Mineral?

SWBAT define mineral; describe SWBAT define mineral; describe how minerals form; identify the how minerals form; identify the

most common elements in earth’s most common elements in earth’s crust. crust.

What do minerals play an important What do minerals play an important part in?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?What is a mineral?

• Mineral– A naturally occurring, inorganic solid with a

specific chemical composition and a definite crystalline structure.

Mineral Characteristics: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: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 SiO2

Mineral Characteristics: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 MagmaMinerals 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 SolutionsMinerals 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 GroupsMineral 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 GroupsMineral Groups

• Sulfides – Compounds of sulfur and one or more elements

• Sulfates – Composed of elements with the sulfate compound

SO4

• Halides – Made up of chlorine or fluoride as well as calcium,

sodium, or potassium

• Native Element– Made up of one element only