1. Add to Table of Contents: Mineral Observations Pg. 24 Minerals of Earth’s CrustPg. 25 Gemstone QuestionsPg. 26 Groups of MineralsPg. 27

2. Groups of Minerals Minerals are grouped by the elements they are made of. Amethyst Beryl (Emerald) Calcite

3. Mineral Group CharacteristicsExamples 1. Silicates Contain Oxygen & Silica Contain Oxygen & Silica The most abundant group of minerals The most abundant group of minerals Make up 96% of the Earth’s crust Make up 96% of the Earth’s crust Quartz (SiO 2 ) mica MICA Quartz

4. Mineral Group CharacteristicsExamples 2. Non- Silicates Do not contain compounds of Silica and Oxygen Do not contain compounds of Silica and Oxygen Make up only 4% of the Earth’s crust Make up only 4% of the Earth’s crust Include some of the most important minerals Include some of the most important minerals  6 different groups.

5. Mineral Group CharacteristicsExamples A. Carbonates Carbon & Oxygen and a positive ion, such as Calcium Carbon & Oxygen and a positive ion, such as Calcium Calcite (CaCO 3 ) Calcite with Duftite inclusions

6. Mineral Group CharacteristicsExamples B. Halides Chlorine or Fluorine combined with Sodium or Potassium. Chlorine or Fluorine combined with Sodium or Potassium.Halite(NaCl) Fluorite(CaF 2 )

7. Mineral Group CharacteristicsExamples D. Sulfides  Sulfur and a metallic ion Galena (PbS) Galena

8. Mineral Group CharacteristicsExamples E. Sulfates  Metallic ion, Sulfur & Oxygen Barite (BaSO 4 ) Barite on Calcite BaSo4 / CaCO3 Barite BaSo4

9. What is a gem? A Mineral OR Rock that has value Rare ! Sometimes polishing or cutting will add value