1. Mineral Identification

2. Physical Properties Individual minerals have unique properties that distinguish them. –Appearance –Hardness »Mohs Scale –Luster –Specific Gravity –Streak –Cleavage –Fracture

3. Mineral Appearance Mineral properties can help you recognize and distinguish minerals. Color and appearance are two obvious clues that can be used to identify minerals. However, both color and appearance can be deceiving and are not enough to determine the identity of a mineral. These both appear to be gold, but only one of them is. The other one is pyrite.

4. Hardness A measure of how easily a mineral can be scratched is its hardness. Diamonds are the hardest mineral. The concept of hardness is sometimes confused with whether or not a mineral will break. A diamond is extremely hard, however it can shatter if hit hard enough.

5. Mohs Scale In 1812, Austrian scientist Freidrich Mohs developed a list of common minerals to compare their hardnessess. This list is called the Mohs scale of hardness. Scale lists the hardness of 10 minerals. These 10 minerals were chosen because they were common or readily available. Talc is the softest mineral, with a value of one. Diamond is the hardest mineral, with a value of 10

6. How Mohs Scale Works Scratch the mineral with different common objects to see if a mark is left on the mineral. If one mineral is harder than the other, it will scratch the softer mineral.

7. Luster The way a mineral reflects light is known as luster. Can be metallic or nonmetallic. Minerals with metallic luster shine like metal. When a mineral does not shine like metal, it has a nonmetallic luster. Metallic Luster Nonmetallic Luster

8. Streak When a mineral is rubbed across a piece of unglazed porcelain tile, a streak of powder is left behind. Streak is the color of a mineral when it is in the powdered form. The streak test works only on minerals that are softer than the streak plate (porcelain tile). More effective way of identifying than color. –Color can be the same in different minerals. You leave streaks from minerals everyday – what are you using?

9. Cleavage The way a mineral breaks is another way to help identify the mineral. Minerals that break along even planes. Will break in thin layers. Just like baking a cake with different layers – you can remove each layer.

10. Fracture Minerals that break with uneven, rough, or jagged surfaces have fracture. »Like grabbing a chunk of cake.

11. Specific Gravity Minerals can also be identified by comparing the weights of equal sized samples. Specific gravity of a mineral is the ratio of its weight compared with the weight of an equal volume of water.