How would a mineral collector determine the hardness of an unknown mineral specimen?

Answer 1

There are two ways. One way is to buy a scratch test kit and follow the instructions. They will tell you to try to scratch minerals of certain hardnesses and find the hardest one it can scratch. For example, if it scratches a mineral with a hardness of 6 but not one with a hardness of 7, the hardness would be between 6 and 7. If you do not have one of those available, you can try scratching common objects. Your fingernail is 1.5, a penny is 2.5, a pocketknife blade is 5.0, window glass is 5.5, a steel file is 6.5, and quartz is 7.0.

Answer 2

You test it with softer things until you see something which won't scratch it:

5.5+:Not scratched by steel nail

3.5+:Not scratched by cooper coin

2.5+:Not scratched by finger nail

Answer 3

Minerals are tested for hardness by performing a scratch test. The unknown mineral is scratched with another object that the hardness is known. For example, a unknown mineral may be scratched with a piece of metal to compare the resistance.

Answer 4

You start by scratching it and seek it's hardness. When you find its hardness, compare it to another mineral with the same hardness. If they look exactly the same, and have the same arrangements of minerals, then they are the exact same mineral.

Answer 5

It's called the Mohs test. You take specimens of known hardness and try to scratch the unknown specimen with a pointed edge of the known specimen. If you can scratch the unknown mineral it is softer, if not it's harder. If you have several mineral samples of known hardness you can narrow down the unknown quickly.