Statistics for Key Properties of Minerals

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Key Property	Mineral	% Correct
Reddish/brown streak	Hematite	81%
Gold color often in cube crystal habit with straiations	Pyrite	69%
Three planes of cleavage at 90 degrees, metallic luster, high specific gravity	Galena	63%
Salty taste, three planes of cleavage at 90 degrees	Halite	63%
Strongly magnetic, distinct black streak	Magnetite	63%
Conchoidal to irregular fracture, could have six sided crystal habit	Quartz	63%
One plane of cleavage, dark to black mica	Biotite	56%
One plane of cleavage, light to white mica	Muscovite	56%
Perfect rhombohedral cleavage, bubbles in HCl	Calcite	50%
Softer than a fingernail, fracture or one plane of cleavage	Talc	50%
Softer than a fingernail, three planes of cleavage not at 90 degrees	Gypsum	44%
Two planes of cleavage at 90 degrees, straiations	Plagioclase Feldspar	44%
Two planes of cleavage at 90 degrees	Augite	38%
Two planes of cleavage not at 90 degrees	Hornblende	38%
Two planes of cleavage at 90 degrees, no striations	Orthoclase Feldspar	38%
Greenish gold in color	Chalcopyrite	25%
Four planes of cleavage (octahedral), hardness between glass and a penny	Fluorite	25%
Green in color, often grainy, harder than glass, fracture	Olivine	25%
Streak smells of sulfur, six planes of cleavage	Sphalerite	25%
Low specific gravity, one plane of cleavage, submetallic luster	Graphite	19%
Rusty streak	Limonite	19%
Conchoidal fracture, dull luster	Chert	13%