Which of the following properties is generally the least useful in identifying minerals?

A.) hardness

B.) streak

C.) cleavage

D.) color

First, you should know that the four properties given are used in the identification of minerals. Hardness is the level of difficulty with which the smooth surface of a mineral sample may be scratched. Cleavage is how the crystal splits along a plane. Color is the result of the reflection of the light by the atoms and Streak is the color displayed by the mineral when it is crushed to a fine powder, while impurity contents affect the color, they do not affect the streak. So, streak is a better technique to identify minerals than colors. And the other two, hardness and cleavage are well known as being very useful. So, the least useful is color. Answer: option D.) color.