16. Which of the following refers to ability of minerals to reflect light on its
surface?
A. Streak
C. fluorescence
B. luster
D. color
17. Which of the following is said to be the most unreliable (variable)
diagnostic property of minerals?
A. luster
B. hardness C. crystal form D.color
18. On Mohs hardness scale, which is the softest mineral?
A. apatite B. calcite C. quartz
D. talc
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