What is a Mineral?

To be considered a mineral, the object MUST possess all 5 of the following characteristics…

5 Things Define a Mineral… 1. Occurs naturally 2. It is a solid at room temperature 3. Definite chemical composition (elements are combined in a definite proportion) 4. Crystal structure due to the internal arrangement of atoms (atoms inside are arranged in an orderly pattern) 5. Inorganic (not living and not formed from anything that was once living)

What defines a mineral?

Mineral or Not? Is quartz a mineral? YES! – all 5 things that define a mineral can be applied to quartz. Is a pearl a mineral? NO! - it is ORGANIC. It is made from secretions of living things. Is glass a mineral? NO! – does not occur naturally

What about Diamond? Is diamond a mineral? YES! – Technically. It’s 10 on Moh’s Hardness scale. What could be the debate about this though??? The debate can be made that it comes from coal and coal is ORGANIC, it’s made from the breakdown of living things like plants.

Mineral Groups Group 1 – The Silicates Made up of Si (silicon) and O (oxygen) plus a metal. Most abundant group of minerals in the world! The silica tetrahedron (1 silicon, 4 oxygen) is the building block of ALL silicate minerals! Examples: –Quartz, mica, feldspars

Mineral Groups Group 2 – The Sulfides Made of S (sulfur) plus a metal Examples: Galena, Sphalerite Group 3 – The Sulfates Made of SO 4 (1 sulfur, 4 oxygens) plus a metal Example: Gypsum

Mineral Groups Group 4 – The Oxides Made of O (oxygen) plus a metal. Examples: Hematite, Magnetite Group 5 – The Halides Made of Cl (Chloride) plus a metal. Examples: Halite (salt), Fluorite

Mineral Groups Group 6 – The Carbonates Made of CO 3 (1 carbon, 3 oxygen) plus metal. Examples: Calcite, Dolomite This group has a special property – the minerals will fizz when acid is applied!fizz Group 7 – The Phosphates Made of PO 4 (1 phosphor, 4 oxygens) plus metal. Example: Apatite

Native Minerals Native minerals are minerals that are made of only one element. Examples: Gold (Au), Silver(Ag), Copper(Cu) Other examples?

Mineral Properties There are several properties that minerals have that can be studied and tested in order to identify an unknown mineral.

Mineral Properties Color Luster Streak Hardness Cleavage Fracture Crystal Form/Shape Density Specific Gravity Magnetism Reaction to acid Taste Fluorescence Double Refraction

Mineral Properties – How do we I.D. a mineral?

Internal Arrangement of Atoms The internal arrangement of atoms in a mineral are what give the mineral most of it’s PHYSICAL properties: Crystal form/shape Hardness Cleavage Fracture

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Some Mineral Pictures! Amethyst Quartz Rose Quartz

Some Mineral Pictures! Galena – Mrs. Weber’s favorite mineral!! Pyrite – commonly known as “fools gold”

Some Mineral Pictures! Muscovite Mica Halite – NaCl - Salt

Some Mineral Pictures! Fluorite Sphalerite

Some Mineral Pictures! Orthoclase Feldspar Hematite

Pg. 16 ESRT! (Back Cover)

More ESRT Help – Pg. 1 (cover)

2.5 Fingernail 3.5 Copper Penny 5.5 Glass 6.5 Steel File 1. Talc 2. Gypsum 3. Calcite 4. Fluorite 5. Apatite 6. Feldspar 7. Quartz 8. Topaz 9. Corundum 10. Diamond Moh’s Hardness Scale 7 Streak Plate Softest Hardest