What is a Mineral?

What is a mineral?

• Solid

• Not liquid, gas, or plasma

What is a mineral?

• Naturally-occurring

• Not man-made

What is a mineral?

• Inorganic

• Never alive

What is a mineral?

• Fixed chemical composition: an element or a compound

What is a mineral?

• Crystal structure: atoms or molecules in an orderly pattern

Most minerals are compounds

• Quartz: silicon and oxygen –SiO2

–Most abundant in earth’s crust

• Halite: sodium and chloride –NaCl

Examples of minerals

Quartz

Halite (rock salt)

Mica

Not minerals

• There are more than 2,000 kinds of minerals, but fewer than 20 are common minerals that form rock

• 10 minerals make up 90% of the earth’s crust

2 Main Types of Minerals

• Silicates and Non-Silicates

Silicates• Contain atoms of silicon

(Si) and oxygen (O)• Forms a tetrahedron• Many contain one or more

different kinds of atoms• Ex. Feldspar – silicon and

oxygen with potassium• SiO2 - Quartz

• 96% of the crust is made of silicates

Non-Silicates: 6 Groups

Native Minerals

• Made up of single elements

Copper

Gold

Sulfur

Halides

• Cation: K, Na, or Ca with an Anion: Cl or F –

• Halite (NaCl)

Sulfides

• Contain an S atom• Ex: Pyrite (FeS2) Fools Gold

Carbonates

• Contains CO3 as part of the compound

• Ex: Malachite Cu2CO3(OH)2

Sulfates

• Contains SO4 as part of the compound

• Ex: Gypsum CaSO4·2H2O

Oxides

• Contains O atom except for silicates, carbonates, and sulfates

• Ex: Hematite Fe2O3