Bellringer: -Describe all the differences you can see between these minerals (use mineral characteristics). -What could be different that you cannot see?

Minerals Types and Classes

The Silicates Silicates: Compound of the elements Silicon (Si) and Oxygen (O). 90% of minerals are silicates because Silicon and Oxygen are the 2 most common elements in Earth’s crust Form from the cooling of Lava/Magma The Si and O join to form Silicon-Oxygen Tetrahedrons

Silicate Minerals: Quartz: There are multiple forms of quartz (rose, amethyst, crystal). Conchoidal Fracture Mohs Hardness: 7 Luster: Glassy

Silicate Minerals Feldspar: The most abundant family of minerals in the Earth’s crust. Can be Plagioclase or Orthoclase Feldspar. 2-3 Directions of cleavage. Mohs Hardness: 6 Luster: Pearly

Silicate Minerals Mica: 2 kinds: Muscovite mica (white mica), and biotite mica (black or brown) One distinct Cleavage (makes long sheets) Mohs Hardness: 2.5 Luster: Pearly

Silicate Minerals Talc: The softest mineral, talcum powder is pure ground up talc. 1 direction of cleavage Mohs Hardness: 1 Luster: Pearly/Oily

Silicate Minerals Olivine: Olive green silicate Belongs to a family where silicates bond to metal ions (Fe/Mg) Ocassionally found in meteors. Conchoidal Fracture Mohs Hardness: 6.5 Luster: Glassy

Silicate Minerals Garnet: A very common gemstone Conchoidal Fracture Hardness: 6-7.5 Luster: Vitreous to resinous

Carbonate Minerals 2nd most common mineral group. Contains the elements carbon and oxygen (CO32-) and one or more metallic elements Examples: Calcite Dolomite

Carbonate Minerals Calcite: Composed of Calcium Carbonate (CaCO3) EFFERVESCENT!!! 3 planes of cleavage Mohs Hardness: 3 Luster: Glassy

Carbonate Minerals Dolomite: Composed of calcium-magnesium carbonate CaMg(CO3)2 Effervescent when scratched or powdered 3 planes of cleavage Mohs Hardness: 3 Luster: Glassy

Halide Minerals Halides: Contain a halogen ion plus one or more elements Formed from salt water evaporation Examples: Fluorite Halite

Sulfide/Sulfate Minerals Minerals that contain the element sulfur and one other element, often metallic Often form from hot water, or solutions Examples: Gypsum Pyrite

Pyrite An Iron Sulfide (Fe3SO4) Occurs in 6 and 12 sided crystals Common Name “Fools Gold” Greenish-Black streak Mohs Hardness: 6.0 Luster: Metallic

Oxide Minerals Hematite (rust) Magnetite Corundum Contain oxygen and one or more other element usually a metal. Can form from magma or from weathering Examples: Hematite (rust) Magnetite Corundum

Hematite The most common Iron Oxide mineral Red to brown streak on streak plate Mohs Hardness: 5 to 6 Luster: Metallic (sometimes earthy if it gets worn down)

Magnetite A black magnetic iron oxide Mineral has magnetic properties Black streak Mohs Hardness: 5.5 to 6.5 Luster: Metallic to Dull

Native Elements Elements that exist in relatively pure forms. Many form from hydrothermal solutions. Examples: Silver, Gold, Copper.

Native Elements Examples (continued): ALLOTROPES OF SULFUR Carbon (Diamond and Graphite) Sulfur (orthorhombic and monoclinic) ALLOTROPES OF SULFUR ALLOTROPES OF CARBON Allotropes are different forms of a single element that exist because of the multiple ways the element can bond to itself.

Mineral Uses Talc – talcum powder Quartz – Glass, Sand Paper, Amethyst Gems Galena - Lead ore Beryl – Emerald Gems Corundum – Ruby Gems Gypsum – Drywall Halite – Rock Salt Copper – Wire, Jewelry, etc… Diamond – Gems, drills