Which mineral is usually used as drilling mud?
A. Hematite
B. Pyrite
C. Barite
D. Gold
How many percents do nonsilicate minerals approximately make up of Earth’s crust?
A. 8
B. 45
C. 62
D. 90
Biotite is the common member of the mica family. It belongs to:
A. Light silicate
B. Dark silicate
C. Nonsilicate
Muscovite is the common member of the mica family. It belongs to:
A. Light silicate
B. Dark silicate
C. Nonsilicate
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