Transcript Minerals
Minerals Chap. 4 • What are Minerals? • Identifying Minerals Which of these are minerals? AMBER COAL MICA PEARL SUGAR QUARTZ HALITE How many types of minerals do you think there are in the earth’s crust? How many types of minerals do you think there are in the earth’s crust? About 3000, but only 30 minerals are common. What are minerals? – 4.1 Objectives • Define a mineral • Describe how minerals form. • Identify the most common elements in Earth’s crust. I. Mineral Mineral Naturally occurring, inorganic solid with a specific chemical composition and definite crystalline structure I. Mineral A. Naturally occurring, inorganic I. Mineral A. Naturally occurring, inorganic B. Solids with specific compositions I. Mineral A. Naturally occurring, inorganic B. Solids with specific compositions C. Definite crystalline structure Crystal Systems Tetragonal Cubic Orthorhombic Hexagonal Triclinic Monoclinic I. Mineral II. Mineral formation A. Some from magma I. Mineral II. Mineral formation A. Some from magma B. Some from solutions III. Mineral Groups III. Mineral Groups A. Silicates Silicates - Made of silicon and oxygen Silicates - Made of silicon and oxygen - Make up about 96% of minerals found in earth’s crust Silicates - Made of silicon and oxygen - Make up about 96% of minerals found in earth’s crust - Include feldspar and quartz. III. Mineral Groups A. Silicates B. Carbonates Carbonates - Made of metal bonded to carbonate, CO32- Carbonates - Made of metal bonded to carbonate, CO32- Found in limestone, malachite and marble III. Mineral Groups A. Silicates B. Carbonates C. Oxides Oxides - Made of metal bonded to oxygen Oxides - Made of metal bonded to oxygen - Hematite Fe2O3 and magnetite Fe3O4 are common iron oxide minerals III. Mineral Groups A. Silicates B. Carbonates C. Oxides D. Halides III. Mineral Groups A. Silicates B. Carbonates C. Oxides D. Halides E. Native Elements III. Mineral Groups A. Silicates B. Carbonates C. Oxides D. Halides E. Native Elements F. Sulfates The End Identifying Minerals 4.2 Objectives • Classify minerals according to their physical and chemical properties • Identify different types of minerals • Discuss how minerals are used I. Mineral Identification I. Mineral Identification azurite A. Color rhodochrosite malachite turquoise I. Mineral Identification A. Color B. Luster (shininess) Luster is the way the mineral surface reflects light. I. Mineral Identification A. Color B. Luster (shininess) 1. metallic pyrite galena I. Mineral Identification A. Color B. Luster (shininess) 1. metallic 2. non-metallic olivine feldspar I. Mineral Identification A. Color B. Luster C. Texture Texture is how a mineral feels to the touch. I. Mineral Identification A. Color B. Luster C. Texture Talc: feels greasy fluorite: feels smooth I. Mineral Identification A. B. C. D. Color Luster Texture Streak Streak is the color of the powder of the mineral. I. Mineral Identification A. B. C. D. Color Luster Texture Streak Hematite: Reddish brown streak Pyrite: Dark grayblack streak I. Mineral Identification A. B. C. D. E. Color Luster Texture Streak Hardness Hardness is a measure of how easily a mineral is scratched. I. Mineral Identification F. Cleavage and Fracture Cleavage means a mineral splits easily and evenly along one or more flat planes. Fracture means a mineral breaks with jagged, rough edges Cleavage or Fracture? Mica: exhibits basal cleavage Cleavage or Fracture? Halite: exhibits cubic cleavage Cleavage or Fracture? Obsidian: exhibits fracture I. Mineral Identification F. Cleavage and Fracture G. Density and Specific Gravity Density is a measure of the mass per unit of volume. I. Mineral Identification F. Cleavage and Fracture G. Density and Specific Gravity H. Other properties I. Mineral Identification F. Cleavage and Fracture G. Density and Specific Gravity H. Other properties 1. refraction Refraction means the bending of light I. Mineral Identification F. Cleavage and Fracture G. Density and Specific Gravity H. Other properties 1. refraction 2. reacting with HCl II.Other terms II.Other terms A. Ores A material for which it is profitable to mine II.Other terms A. Ores B. Gems Valuable minerals prized for rarity and beauty The End