Understanding Minerals: Basic Info, Formation, and Economic Importance

1. Chapter 4Basic Info on Minerals!

2. Mineral Video http://www.youtube.com/watch?v=8a7p1NFn64s

3. Mineral Properties • Inorganic • Didn’t come from anything that was once alive) • Solid (at room temp) • Ice is not a mineral • Naturally occurring • Not man made • Specific chemical composition • May have some variations, but elements are same throughout • Definite crystalline structure • Crystals may be microscopic due to rapid cooling

4. Mineral or Not? • Coal • Not • It’s organic • Diamond • Mineral • Dried mud • Not • No definite crystalline structure

5. Mineral or Not? • Cubic zirconium • Not (man-made diamond imitation) • Salt • Mineral • NaCl, inorganic, cubic crystals • Sugar • Not • Organic • Copper • Mineral

6. What are minerals made of? • Minerals are made of … • elements (Carbon, C, makes up diamonds), • or … • Compounds (quartz is made of silicon dioxide, SiO2) • Can you think of another example of minerals made of compunds? • Salt is made of sodium chloride • (NaCl)

7. Minerals are the Building Blocks of Rocks • Rocks are made of minerals • Granite is made up of feldspar, quartz and often other minerals • There are thousands of minerals • But only about 30 minerals are common • Of the 30, 8-10 make up most of the rocks on earth:

8. 8 most common minerals • Quartz • Feldspar • Mica • Pyroxene • Amphibole • Olivine • Garnet • Calcite

9. Elements are Mineral Building Blocks • The common rock-forming minerals are mostly made up of the most common elements in earth’s crust.

10. Most Common Elements in Earth’s Crust • Oxygen (O) 46.6% • Silicon (Si) 27.7%

11. Most Common Elements in Earth’s Crust • Aluminum (Al) 8.1% • Iron (Fe) 5%

12. Most Common Elements in Earth’s Crust • Calcium (Ca) 3.6% • Sulfur (S) 2.8%

13. Most Common Elements in Earth’s Crust • Potassium (K) 2.6% • Magnesium (Mg) 2.1%

14. How do Minerals Form? Part I • What do you call the molten material that is below the earth’s crust? • Magma • Which is less dense, magma or the surrounding solid rock? • Magma, so it is always pushing up on the crust

15. How do Minerals Form? Part I • What kinds of places allow magma to rise? • Volcanoes, • places where the crust is separating and • places where the crust is very thin (Yellowstone Park)

16. How do Minerals Form? Part I • When magma rises and cools, it forms into minerals • Quick cooling  very small crystals • Slow cooling  larger crystals • Different magma composition  different minerals

17. How do Minerals Form? Part II • Often, minerals are dissolved in water • Ever heard of mineral water???? • If the water contains enough of the mineral, it will begin to crystallize in the water Rock Candy = water saturated with sugar + time

18. How do Minerals Form? Part II • We call water that contains so much mineral that it crystallizes out to be… • Supersaturated • Also, crystals can form when the water the mineral is in evaporates

19. Economic Minerals • Minerals are everywhere and used for many things • Look around the room. Can you see anything made of minerals? • The ceiling is made from gypsum (wall board, etc) • Your pencil “lead” is graphite • All metals are minerals • Glass is melted down sand, essentially • Computer chips are silicon

20. Economic Minerals • A mineral is an _____ if it contains a useful substance that can be mined at a profit • ore • _____ are minerals that are prized for their rarity and beauty. Usually perfect crystals • gems