How do geologists know that diamond is the hardest mineral?
A) They conduct molecular analyses.
B) They conduct a crush test.
C) They conduct a scratch test.
D) They conduct a streak test.

Question

Quizplus · Accepted Answer

Geologists know that diamond is the hardest mineral by conducting a scratch test. This test involves using a diamond-tipped tool to scratch the mineral's surface. If the mineral scratches easily or is scratched by the tool, then it is not as hard as diamond. However, if the mineral can scratch the diamond, then it is not only hard but also harder than diamond. This test is used to determine the relative hardness of minerals on the Mohs scale.

How Do Geologists Know That Diamond Is the Hardest Mineral