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What are minerals? How are minerals identified?. Pyrite or “Fool’s Gold”. Gold. Minerals are …. Nonliving (inorganic), solid substances. They occur natural ly and have a repeating structure (crystal structure due to internal arrangement of atoms). How are minerals used?.
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What are minerals?How are minerals identified? Pyrite or “Fool’s Gold” Gold
Minerals are … Nonliving (inorganic), solid substances. They occur naturally and have a repeatingstructure (crystal structure due to internal arrangement of atoms).
How are minerals used? • Aluminum can be used for packaging, transport, and building. • Beryllium is used in gemstones and fluorescent lights. • Copper is used in electric cables, wires, and switches. • Feldspar is used in glass and ceramics. • Calcite is used in toothpaste and construction. • Iron is used in buildings, automobiles, and magnets. • Titanium is used in airplanes. • www.mii.org/commonminerals.php
How are minerals identified? • Minerals can be identified by their properties. • Color • Streak • Hardness • Luster • Cleavage • Fracture
Color • Minerals come in a rainbow of colors. • Minerals can change color when exposed to air and rain for a long time. • A mineral can have different colors. • Color alone cannot be used to identify a mineral. Malachite
Streak • Streak is the color of the powder left behind when a mineral is rubbed against a streak plate. A streak plate is a rough white tile. Hematite with its reddish streak. Pyrite with its greenish-black streak. Galena with its dark gray-black streak.
Hardness • Hardness is a mineral’s ability to scratch other materials or be scratched by other materials. • Mohs’ hardness scale ranks minerals from 1 to 10 according to their hardness. • Talc, the softest mineral, is 1. • Diamond, the hardest mineral, is 10. • A mineral can scratch another mineral if its hardness value is greater than or equal to the other mineral’s hardness. Mohs’ Hardness Scale
Luster • Luster is the way a mineral’s surface reflects light. • Metallic luster (how light reflects off metals such as gold, silver, and copper) • Nonmetallic luster (described as glassy, silky, waxy, pearly, earthy, or resinous-like plastic) Tourmaline has a glassy luster.
Cleavage • Cleavage is the way that some minerals break into pieces with smooth, flat, regular shapes. • Quartz is one of Earth’s most common minerals. This crystal forms as a six-sided prism with pointed ends. The ends look like six-sided pyramids. www.sdnhm.org/fieldguide/minerals/index.html
Fracture • Fracture is the property of breaking unevenly or along a curved surface. Copper has an uneven or irregular fracture.
Special Characteristics“The Acid Test” You can test minerals by putting them in vinegar. If it instantly reacts (fizzing or bubbling – releasing CO2 gas), it is probably a carbonate mineral like calcite.
Special CharacteristicsFluorescence • Some minerals will glow when placed under short-wave or long-wave ultraviolet rays. • Franklin and Ogdenberg, NJ are famous for their fluorescent minerals. Calcite (red) and willemite (green) Glowing under shortwave ultraviolet light.
Special Characteristics Magnetism • Many iron minerals will produce an invisible magnetic force field. • “Lodestone” was used by Vikings more than a thousand years ago as compasses. Magnetite