3. Scientific Definition Minerals are….. I.Naturally occurring II.Inorganic III.Solids IV.With definite chemical compositions, V.And ordered atomic structures

4. http://www.mii.org/ Minerals are economically important

5. Formation of minerals Anything that changes from liquid to solid forms crystals (not just “rocks”) Snow flakes are crystals Sugar and salt are crystals http://www.youtube.com/watch?v=czmQ2_ym aOo

6. Physical Characteristics include... ColorColor Fracture/CleavageFracture/Cleavage HardnessHardness **Note that size is not a physical characteristic LusterLuster StreakStreak Specific GravitySpecific Gravity

7. ColorColorColorColor Color of some minerals is a very useful characteristic to use in identifying them. Sometimes it is not This sulfur for example is almost always yellow. Quartz can be almost any color

8. Luster is the way in which a mineral reflects light, or the way that it shines. Luster may be “Metallic”... Or Non MetallicLuster is the way in which a mineral reflects light, or the way that it shines. Luster may be “Metallic”... Or Non Metallic If it looks shiny like metal, its metallicIf it looks shiny like metal, its metallic

9. This is the metallic luster of the mineral Galena

10. Or it may be “non-metallic” Non-metallic mineral luster’s include such descriptions as earthy, glassy,Non-metallic mineral luster’s include such descriptions as earthy, glassy, dull, or silky.

11. Or Earthy like

12. Streak is the color of the powder left behind when the mineral is rubbed on a piece of unglazed porcelain.

13. Hardness is a mineral’s resistance to being scratched. NOT ITS RESISTANCE TO BREAKING!!! A numerical scale from 1- 10 is used to measure hardness. (Moh’s Scale) Talc is the softest mineral at #1. Diamond is hardest (#10)

15. Specific gravity is the ratio of a mineral’s mass compared to an equal volume of water. In other words, how many times heavier is the mineral than the same amount of water? (a.k.a. Density)

16. is the way in which a mineral breaks. If the mineral breaks along smooth flat surfaces like calcite or mica, it is said to cleave.

17. Some minerals break along parallel planes of weakness This is due to the internal arrangement and bonding of their atoms. http://www.youtube.co m/watch?v=iafahWbrK 5Y (5 min) in.http://www.youtube.co m/watch?v=iafahWbrK 5Y

18. Fracture refers to the characteristic of breaking along rough irregular surfaces. Mineral like quartz and garnet are said to “fracture”.Fracture refers to the characteristic of breaking along rough irregular surfaces. Mineral like quartz and garnet are said to “fracture”. Think of a meat cleaver and a bone fracture to keep these terms straight.

19. These properties of mineral crystals are determined by 1. It’s chemical make-up 2. the arrangement of its atoms.