1. Rocks and Minerals Rocks are made of minerals, which are solid nonliving substances formed by natural processes in or on the Earth.

2. Types of minerals Metallic minerals = tin, iron, copper, silver, gold, etc. Nonmetallic minerals Gemstones = diamonds, rubies, emeralds, etc Rock-forming minerals = quartz, mica, hornblende

3. 3 Types of rocks Igneous Sedimentary Metamorphic

4. Igneous Rock, formed from cooled lava or magma Intrusive = cooled magma trapped in underground cracks and openings May take thousands of years to cool Crystals have time to grow Coarse texture

5. Igneous Intrusions

6. Intrusive Igneous Rock: Pegmatite

7. Extrusive = cooled lava (above ground) Cooled very quickly Very small or no crystals, may be glassy or full of holes

8. Extrusive Igneous Rock : Obsidian

9. Sedimentary Rock, formed from broken bits of rocks, minerals, living things, or dissolved minerals

10. Compaction: sediments build up in layers, bottom layers turned to rock by pressure Cementation: coarse sediments held together by pieces of rocks or minerals

11. Plant and animal remains change chemically and harden Sediments dissolved in water crystallize as water evaporates

12. Types Detrital or Clastic, from broken bits of rocks and minerals Chemical, from minerals dissolved in water Organic, from substances that were once alive

13. How Coal Forms

14. White Sandstone

15. Conglomerate

16. Metamorphic rock, rock changed from one type to another by great heat, pressure, or chemical change. Happens mostly underground (high heat and pressure)

17. Types Foliated rock, minerals arranged in layers as they recrystallize or are flattened under pressure Nonfoliated rock, not formed in layers

18. Foliated: Hornblende gneiss

19. Nonfoliated: Marble