1	MINERALS
2	Minerals are important They’re pretty AND Minerals are important because: They tell us the history of a rock The source of a rock Economic or health value
3	Value of a Mineral Gemstone Beryl = aquamarine, emerald Corundum = ruby Fertilizer Carnallite Consumption Halite = table salt Ores Colemanite = boron, paint, glass, rocket fuel
4	What defines a mineral? Orderly atomic arrangement Specific chemical structure Solid Naturally occurring Inorganic Have a set of physical properties used to identify them
5	Minerals and Elements Minerals are made up of 2 or more elements The most common elements in the earth’s crust are: Oxygen Silicon Aluminum Iron Calcium Sodium Potassium Magnesium
6	Minerals Classified by chemical composition and structure Classes include Silicates Carbonates Sulfates Oxides Hydroxides Phosphates Silicate minerals most abundant in the earth’s crust Includes Quartz, micas, feldspars, garnets
7	Identifying Minerals Megascopic 6 major identifying properties Microscopic Optical mineralogy X-rays
8	Physical Properties of Minerals Crystal Form orderly internal arrangement of atoms Only see if mineral allowed to grow naturally
9	Physical Properties of Minerals Luster Appearance or quality of light reflected from the surface of a mineral Metallic Non-metallic Glassy, dull, pearly, etc.
10	Physical Properties of Minerals Streak Color of a mineral in its powdered form More reliable than color of the whole mineral
11	Physical Properties of Minerals Hardness Measure of the resistance to abrasion or scratching Can be affected by impurities
12	Physical Properties of Minerals Breaking habits Cleavage Tendency of a mineral to break along planes of weakness Mineral breaks into pieces with same geometry Excellent, good, poor or no cleavage If more than one cleavage plane, described by angles at which they meet Fracture Conchoidal or irregular
13	Cleavage Directions
14	Cleavage Directions
15	Cleavage Directions
16	Physical Properties of Minerals Specific Gravity weight of mineral weight of equal volume of water Higher specific gravity => denser mineral Heft mineral in hand to estimate
17	Physical Properties of Minerals Other physical properties Optical properties: Transparent: image visible through mineral Translucent: light-not image-visible Opaque: no light transmitted Taste Magnetism Smell Carbonates fizz when exposed to acid
18	Physical Properties of Minerals Color WARNING!! Unreliable diagnostic property
19	Rocks!
20	Introduction to Rocks Definition: an aggregate of one or more minerals 3 types of rocks Igneous Extrusive (volcanic) Intrusive (plutonic) Sedimentary Metamorphic Rocks are identified by Texture Assemblage of minerals
21	Rock Cycle Describes the interrelationships of geology Dynamic cycle of formation, change, and destruction May be interrupted or redirected at any stage!
22	Rock Cycle