1. BAESI: Minerals November 19, 2011 Ellen Metzger

2. Bay Area Earth Science Institute  Since 1990  Web Site: www.baesi.org “One-stop shopping” A collection of podcasts, ready-to-use classroom activities, and other resources for teaching about plate tectonics, climate change, and other topics

3. Acknowledgements  The BAESI Saturday workshop program is made possible by a grant from Chevron.  Geologic maps of California supplied by the Northern California Geological Society and the American Association of Petroleum Geologists Foundation.

4.  What is a mineral?

5. What is a Mineral? A mineral is a naturally-occurring, inorganic solid with a definite (but generally not fixed) chemical composition and an orderly internal arrangement of atoms (crystalline). Examples of chemical formulas for minerals: Quartz: SiO 2 Pyrite: FeS 2

6. Crystalline Halite - NaCl Definite chemical composition Orderly arrangement of atoms

7. Both are crystalline http://skywalker.cochise.edu/wellerr/VGM/mineral-hall.htm Virtual Geology Museum at Cochise College – Copyright-free phtos

8. http://www.slideshare.net/johnthebillionaire/naica-crystal-cave-80324

9. "Walking into either of these caves is like stepping into a gigantic geode," said Richard D. Fisher, an American consultant with the mining company to develop the discoveries as tourist attractions. Fisher said that most people can endure only a few minutes in the caves due to their high temperatures.

10. Mineral Identification  What properties can be used to identify minerals?  What do you observe?

11. Physical properties used to identify minerals  Color  Streak  Luster  Hardness  Cleavage/fracture  Specific gravity (“heft’)  Reaction with dilute HCl (or vinegar)  Magnetism  Crystal habit or form

12. Color All of these are quartz.

13. Two Forms of Hematite: Same Streak http://www.li-edu.com/hematite.gif http://www.belmont.sd62.bc.ca/teacher/geology12/photos/minerals/streak_hematite.jpg

14. Luster  Pyrite: Metallic Luster  Halite: Nonmetallic Luster Shiny does not equal metallic.

15. Moh’s Scale of Hardness 1 = Talc 2 = Gypsum 3 = Calcite 4 = Fluorite 5 = Apatite 6 = Orthoclase 7 = Quartz 8 = Topaz 9 = Corundum 10 = Diamond Hardness of everyday objects Fingernail: 2.5 Penny ~ 3.5 Glass and a steel nail: 5.5 and

16. Examples of Cleavage http://upload.wikimedia.org/wikipedia/commons/9/93/Mineral-cleavage.gif Look for signs of breakage: “steps” on mineral surfaces

17. Fracture: Irregular Breakage http://geophysics.ou.edu/geol1114/notes/minerals/conchoidal.jpg Quartz has conchoidal (curving fracture)

18. California’s Unique Rocks and Minerals  Blueschist  Graywacke  Serpentinite

19. California’s Non-fuel Mineral Production, 2007

20. California’s Mineral Resources  What is our state gem?  Our state mineral?  Our state rock?