1. Ch. 13 Minerals  Minerals are naturally formed solids with a crystalline structure  Minerals are made of atoms and compounds  Crystals have definate shapes  EXAMPLE: Table salt (NaCl) has a definate shape and is made of two elements

2. Silicate vs. Nonsilicate  Silicate minerals make up 90% of the Earth’s surface; have a combo. Of oxygen, silicon and at least one metal like iron or aluminum.  Nonsilicate minerals do not have the silicon-oxygen combo.

3. Properties  Color  Luster: how dull or shiny; different types on p. 340  Streak: using a streak plate, the mineral may leave a different color powder when pulled across the plate  Cleavage and Fracture: how the mineral breaks (important in jewelry)  Mohs Hardness Scale: ranges from 1 (soft) to 10 (hard); does NOT have a set measurement  Density: used to compare the minerals to water