Imagine you are handed a mineral sample. It breaks with a conchoidal fracture, but displays no cleavage. It does not react with hydrochloric acid, is a light pink color, and has a nonmetallic luster. It is harder than a streak plate, and has a specific gravity of 2.65. What mineral is it?
A)olivine
B)potassium feldspar
C)calcite
D)quartz

Question

Quizplus · Accepted Answer

The mineral has a conchoidal fracture and no cleavage, which are characteristic of quartz. It also does not react with hydrochloric acid, has a nonmetallic luster, and a specific gravity of 2.65, all consistent with quartz. Its pink color does not rule out quartz since there are many different colors of quartz, including pink. The fact that it is harder than a streak plate indicates that it has a hardness of at least 7 on Mohs scale, which is the hardness of quartz. Therefore, the mineral is quartz (choice D).

Imagine You Are Handed a Mineral Sample