MINERAL name LUSTER (appearance) HARDNESS DISTINGUISHING properties
Pyrite Metallic Slightly harder than glass Hardness greater than glass (H ~ 6-6.5); Brassy yellow color; black color streak; Crystals commonly cubic; no cleavage.

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Galena Metallic Softer than glass 3 perfect cleavages in ~ 90 degrees, high density.
Hematite Metallic or non-metallic luster Hard to tell, however harder Red-brown streak.
Hornblende Non-metallic (black) Harder than glass Usually black or dark green; 2 cleavages in ~ 60°/120° (56°/124°)
Biotite Non-metallic (black) Slightly harder 보다 glass 1 perfect cleavage; Dark brown-black color, faint yellow-brown streak.
Olivine Non-metallic (green) Slightly harder 보다 glass Olive environment-friendly color; Granular; Conchoidal fracture; Hardness greater than glass (H ~ 6.5 – 7).
Plagioclase Feldspar Non-metallic (med. Grey to irradiate grey) Slightly harder than glass 2 cleavages at about 90°; Striations (twinning) present; can be white come dark gray.
Potassium Feldspar Non-metallic (Pink to white) Slightly harder than glass 2 cleavages at around 90°; Striations no present; deserve to be pink, white (sometimes green).
Quartz Non-metallic (any color) Harder than glass Hexagonal crystals; No cleavage planes; Conchoidal Fracture; Hardness better than glass (H=7 ~ above Moh’s scale).
Muscovite Non-metallic (gold-clear) Softer than glass 1 perfect cleavage; Colorless or silvery appearance, once offered for window glass; Ke$ha likes it.
Fluorite Non-metallic (purple, green, yellow) Softer than glass softer than glass; FOUR cleavage planes!
Calcite Non-metallic Softer than glass 3 perfect cleavages not at 90° (rhombohedral cleavage); Fizzes readily once HCl mountain applied.
Halite Non-metallic Softer than glass 3 perfect cleavages at 90°; Tastes prefer salt, feel greasy.

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Gypsum Non-metallic Softer 보다 glass and softer 보다 a fingernail Generally clear to white; One perfect cleavage, may display up come 3 cleavages; Easily scratched through a fingernail.

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