TGMS Show Quiz! TGMS Show – Quiz Case Name(Required) First Last Phone(Required)Email(Required) 1. Cactus quartz is found mostly in the southern half of Arizona. True False 2. Many mineral collectors have a specimen or two of β-Quartz from Arkansas. True False 3. Quartzite, Arizona is the type locality for quartz. True False 4. Petrified or silicified wood is a quartz pseudomorph. True False 5. Quartz is the most abundant mineral in the earth’s crust. True False 6. Both quartz and topaz are hard minerals, both having a Mohs hardness scale of 8. True False 7. Obsidian forms near active volcanoes, is approximately 70% silica, and considered to be non-crystallized silica. True False 8. Agates mostly form as nodules within volcanic rocks. True False 9. Yellow quartz is called citrine. Most citrine specimens or gemstones are generated from heated amethyst. True False 10. High voltage powerline arcing onto sandy soil can produce the silica mineraloid lechatelierite. True False 11. All gwindel quartz specimens are from the European Alps. True False 12. Double-terminated clear Herkimer diamonds (quartz crystals) can be found in the Alps. True False 13. Amethyst owes its color to gamma irradiation and presence of trace iron. True False 14. Coesite was first described from Meteor Crater in 1954 by Loring Coes. True False 15. Australia is still the largest producer of opals. True False 16. Lake Superior agate is the designated state mineral of Minnesota. True False