1. IN: If you had to describe how one mineral is different from another, how might you describe its properties?

2. 3-2 IDENTIFYING MINERALS  How are these two minerals are the same? How are they different?

3. PROPERTIES OF MINERALS  Color  Luster  Streak  Cleavage and Fracture  Hardness  Density  Special Properties

4. COLOR  The same mineral can come in different colors.  Impurities  Quartz-white, red, pink, and purple  Weathering  Pyrite turns black  Color is not a very reliable indicator of a mineral’s identity.

5. LUSTER  The way a surface reflects light. (How it Shines)  There are 3 types: 1. Metallic 2. Submetallic 3. Nonmetallic (vitreous, silky, resinous, waxy, Pearly or Earthy)

6. METALLIC LUSTER  Looks shiny, like metal.

7. NONMETALLIC LUSTER  Does not look like metal. Vitreous quartz Pearly talc Earthy psilomelane

8.  Has properties of both metallic and nonmetallic. Hematite

9. STREAK  The color of a mineral in a powdered form. (shows its “true color”)  The color of a mineral is not always the color of its streak.

10. STREAK  A minerals streak is not affected by weathering.  Therefore, a mineral’s streak is much more reliable than its color.

11. CLEAVAGE  The tendency of some minerals to break along flat surfaces.

13. FRACTURE  The tendency of some minerals to break unevenly along curved or irregular surfaces.

14. HARDNESS  A mineral’s resistance to being scratched.

15. DENSITY  The measure of how much matter there is in a given amount of space.  Remember the density of water=1g/mL

16. SPECIAL PROPERTIES  Properties that are particular to only a few types of minerals.

17. SPECIAL PROPERTIES  Fluorescence

18. CHEMICAL REACTION  Calcite will “fizz” with acid

19. OPTICAL PROPERTIES

20. RADIOACTIVITY  Uranium

21. MAGNETISM  Magnetite

22. TASTE  Halite  Tastes “salty”

24.  OUT: How would you summarize the seven properties of a mineral?