PSNB+4.1

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=4.1 Properties of Minerals=

Vocabulary
Inorganic: A mineral that cannot come from minerals of something living. Crystal: A repeating pattern of some mineral particles that from a solid. Element: A substance made from different things. Compounds: Two different elements combined to make one. Mohs Hardness Scale: Ranks 10 certain elements from soft to hard. Streak: The color of the powder of a mineral. Luster: A term that explains how a mineral reflects light from it's surface. Cleavage: Minerals that split easily on open surfaces. Fracture: Describes ho0w a mineral breaks and how it looks. Fluoroesence: Minerals that grow under ultra- violet light.

What is a mineral?

 * A mineral is a naturally occurring, inorganic solid with crystal structure and definite chemical composition
 * Naturally Occurring**
 * Cannot be man made (glass, brick) must be __naturally occurring__
 * Inorganic**
 * Mineral can't get created from materials that were part of a living thing.
 * Solid**
 * Must be solid with definite shape/volume (particles can't flow freely in a solid)
 * Crystal Structure**
 * Crystals are formed when pattern repeats over and over again
 * Definite Chemical Composition**
 * Should have elements in definite proportions (that creates a compound)
 * Some minerals are pure, or not created by two elements

Identifying Minerals

 * Each mineral has its own __specific__ properties that can identify it
 * Hardness**
 * Mohs scale rates 1-10, softest to hardest
 * Mineral can scratch any mineral softer than it, but will be scratched by harder ones


 * Color**[[image:Science_psnb_4.1 width="758" height="444"]]
 * Some minerals have more than one color, not reliable source
 * Streak**
 * Color of mineral's powder
 * Can be measured by rubbing mineral against streak plate (unglazed tile)
 * Each mineral __always__ has its own streak, no matter what color it is.
 * Luster**
 * How mineral reflects light from its surface
 * Density**
 * Measured by weight, scientists use a scale
 * Crystal Systems**
 * All have different crystal structures
 * Cleavage and Fracture**
 * If it splits easily along flat surface, it has cleavage
 * Depends on ho crystals and atoms are arranged, Split in different ways.
 * Minerals that don't split easily have fracture
 * rough, irregular surfaces have an uneven fracture
 * Special Properties**
 * Some minerals have unique strange properties (magnetism, etc.)

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