The document discusses minerals, their properties, and how they are classified. It defines minerals as naturally occurring solid substances with a crystal structure. All minerals share common characteristics - they form through natural processes, are not living, have a definite shape and volume, and are made of elements or compounds arranged in repeating crystal patterns. Minerals are grouped based on their chemical composition, with the most abundant group being silicates like quartz and mica. Physical properties like color, luster, hardness, cleavage/fracture, and specific gravity can be used to identify different minerals.

1. Minerals

2. What is a Mineral? Naturally-formed solid substance with a crystal structure Pyromorphite

3. What do all minerals have in common? All: Are formed by natural processes. Are NOT alive and NEVER were alive Have a definite volume and shape Are elements or compounds with a unique chemical makeup Are made up of particles that are arranged in a pattern that is repeated over and over (called a CRYSTAL )

4. Watch “Crystals” by Brainpop… .What element are diamonds made from? . What do all crystals have in common?

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

6. MICA Quartz Quartz, mica Contain oxygen & silica The most abundant group of minerals Silicates Examples Characteristics Mineral Group

7. Silver Gold Ruby Iron Copper Diamond iron, copper, gold, silver, diamonds, rubies Make up only 5% of the Earth’s crust Include some of the most important minerals Non-Silicates Examples Characteristics Mineral Group

8. Calcite with Duftite inclusions Calcite (CaCO 3 ) Carbon & oxygen and a positive ion, such as calcium Carbonates Examples Characteristics Mineral Group

9. Hematite (Fe 2 )O 3 Metallic ion and oxygen Oxides Examples Characteristics Mineral Group

10. Galena (PbS) Sulfur and a metallic ion Sulfides Examples Characteristics Mineral Group

11. Barite on Calcite BaSo4 / CaCO3 Barite BaSo4 Barite (BaSO 4 ) Metallic ion, Sulfur & oxygen Sulfates Examples Characteristics Mineral Group

12. Gold (Au), Diamond (C), Silver (Ag) Single elements Native Elements Examples Characteristics Mineral Group

13. How do minerals form? 1) Cooling of magma (hot, liquid rock and minerals inside the earth (from the mantle)) Fast Cooling = No Crystals (mineraloids) Medium Cooling = small crystals Slow Cooling = large crystals

14. How do minerals form? 2) Elements dissolved in liquids (usually water)

15. Physical Properties of Minerals (can be used to identify the mineral) Color Can be misleading Can vary with the type of impurities

16. Physical Properties of Minerals (can be used to identify the mineral) Luster Surface reflection metallic = shiny like metal non-metallic = dull, non-shiny surface Pyrite has a metallic luster Calcite has a non-metallic luster

17. Physical Properties of Minerals (can be used to identify the mineral) Streak The color of the powdered form of the mineral The color of the streak can be different than the mineral Minerals must be softer than the streak plate

18. Streak…can help identify quartz BUT... http://www.childrensmuseum.org/geomysteries/cube/b3.html

19. Physical Properties of Minerals (can be used to identify the mineral) Hardness How easily a mineral scratches materials Mohs Hardness Scale Scale from 1 ( softest ) to 10 ( hardest ) Test by seeing if the mineral can scratch different objects (like human fingernail, copper, penny, glass, steel file)

20. Find out more… “ Electronic” Hardness Test http://www.childrensmuseum.org/geomysteries/cube/b2.html

21. Physical Properties of Minerals (can be used to identify the mineral) Cleavage & Fracture The way the mineral breaks Cleavage —minerals break along smooth , flat surfaces and every fragment has the same general shape Fracture —minerals that break at random with rough or jagged edges

23. Cleavage or Fracture? 1. 4. 3. 2.

24. Physical Properties of Minerals (can be used to identify the mineral) Other Properties Specific gravity (*excellent clue to mineral’s identity) Attraction to magnets Bending of light Reaction with hydrochloric acid Smell & taste http://www.childrensmuseum.org/geomysteries/cube/b4.html

25. Watch Brainpop—“Mineral Identification” . If a mineral can scratch your fingernail, the mineral is _______________ than your fingernail. 2. What is luster?

26. Watch Classifying Minerals Clip

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