Question

What is the streak given by garnet?

(a) White

(b) Black

(c) Grey

(d) No colour

The question was posed to me in an interview.

This question is from Formation and Descriptive Study of Minerals in section The Study of Minerals of Engineering Geology

Answer 1

The correct answer is:

(d) No colour

Explanation: Garnet typically has a no color streak, meaning when it is rubbed across a porcelain plate, it does not leave any streak or powder behind. This is because garnet is a relatively hard mineral, and its streak is not usually visible.

Here’s a bit more detail about the other options:

• White: Some minerals like gypsum or talc might have a white streak, but not garnet.
• Black: Minerals like magnetite might leave a black streak, but garnet does not.
• Grey: Some minerals, such as graphite, can have a grey streak, but garnet doesn’t leave a streak.

Thus, (d) No colour is the correct answer for garnet’s streak