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Learn about minerals, their properties, how they are formed, and how to identify them using physical characteristics. Discover the different types of minerals and their uses in various industries.
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Proceed to your notes! Fill in all notes for the Mineral Section ( pages 1-2)
Minerals are….. • INORGANIC ( are not and never were living) • NATURAL(not made by humans) • SOLID • Definite CHEMICAL COMPOSITION • CRYSTAL STRUCTURE due to internal arrangement of atoms Hope Diamond All minerals are CRYSTALLINE, but not all are PERFECT CRYSTALS!
Are all rocks minerals? • No. All minerals are rocks, but not all rocks are minerals. • Many rocks are composed of organic material (ex: coal)
Is it a Mineral? • Now that you know what a mineral is. Let’s take a look at some objects and determine whether they are minerals or not.
Minerals Facts • Between 3 - 4,000 have been identified • few are “native elements” ( gold, Au) • Most are compounds, especially the silicate group (Si, O). • Other important groups are oxides, carbonates, and sulfides.
Common uses include: • Aluminum--packaging, transport, building • Beryllium--gemstones, fluorescent lights • Copper--electric cables, wires, switches • Feldspar--glass and ceramics • Iron--buildings, automobiles, magnets • Calcite--toothpaste, construction Guess for STAMPS!
Mineral Formation • Cooling and solidification ofmagma Ex. ruby • Precipitates from water, by evaporation Chemical reactions. Ex. malachite • High temps and pressure rearrange atoms in existing minerals to form new ones Ex. Garnet
Mineral Identification You NEED………………. • Glass Plate • Streak Plate • Copper Penny • Nail • HCl • Magnifying Glass • ESRT pg. 16 • Physical properties are most useful from Amethyst Galleries
COLOR • COLOR • Easiest to recognize, worstto identify a mineral • Color can be due to chemical comp. & impurities
STREAK • STREAK • Streak Color for a Few Common Minerals • Black - Graphite • Black - Pryite • Black - Magnetite • Black - Chalcopyrite • Gray - Galena • Limonite - Yellow-brown • Hematite - Red-brown • Color of the mineral’s powder • Good method of identification • use a streak plate
LUSTER • LUSTER • How the mineral reflects light vs. Metallic Non-Metallic • Shines like a polished metal • Dull, pearly, earthy • Can shine like glass - vitreous
HARDNESS • HARDNESS • Minerals resistance to being scratched • Determined by internal arrangement of atoms, & chemical bonds • Use Moh’s Scale of Hardness
CLEAVAGE • Cleavage • The way a mineral naturally breaks or splits • Clean breaks along at least one side ( Flat)
FRACTURE • Does not break with flat sides (uneven) • Conchoidal Fracture: Breaks like glass: sharp edges
Native Elements • A group of minerals that exist in pure form • Au, Ag, Cu, S, C
Carbonates • Minerals that contain both carbon and oxygen • Calcite
Oxides • Minerals that contain oxygen and usually a metal • Hematite and Corundum
SILICATES • Any mineral containing Silicon and Oxygen (SiO4) • Forms a Silicon-Oxygen Tetrahedron • Examples: • Quartz • Mica • Hornblende • Feldspar • Pyroxene
SILICATES • Most abundant minerals on Earth ESRT • One tetrahedron can make many different looking crystals • The internalarrangementof the atoms determines the properties of the mineral! Put them together in sheets and you get mica
Chain SILICATES in chains and you get hornblende
Crystal Shape (Form) • External structure due to internal arrangement of the atoms • Six basic groups of shapes, with about three dozen variations http://www.minerals.net/mineral/carbonat/aragonit/aragoni1.htm
Carbonates react with dilute HCl and other acids by fizzing or bubbling (releasing CO2 gas) Special Characteristics--the “Acid Test”
Special Characteristics-- Fluorescence • Some minerals will glow when placed under short-wave or long-wave ultraviolet rays • Franklin and Ogdensburg NJ are famous for their fluorescent minerals http://www.sterlinghill.org/Tour%20information.htm
Special Characteristics--Salty Taste • DO NOT TASTE THE MINERALS! • Halite is the exception--it will taste salty http://mineral.galleries.com/scripts/item.exe?LIST+Minerals+Halides+Halite
Special Characteristics--Magnetism • Many iron minerals will produce an invisible magnetic force field • “Lodestone” was used by Vikings more than 1,000 years ago as compasses http://www.minerals.net/mineral/oxides/magnetit/magneti4.htm