A chart titled Mohs Hardness Scale shows minerals of increasing hardness, starting at 1 and increasing to 10. Talc has a hardness of 1. Gypsum has a hardness of 2. Calcite has a hardness of 3. Fluorite has a hardness of 4. Apatite has a hardness of 5. Feldspar has a hardness of 6. Quartz has a hardness of 7.Topaz has a hardness of 8. Corundum has a hardness of 9. Diamond has a hardness of 10.
A mineral is scratched by apatite but not by calcite. What could its hardness value be?
(1 point)
Responses
1
1
2
2
4
4
6
6
1 answer
A mineral that is scratched by apatite (hardness 5) but not by calcite (hardness 3) must have a hardness value between 3 and 5. This means the mineral's hardness could be 4 or 5. Since it is not scratched by calcite, it cannot be 3 or lower.
So the only appropriate hardness value from the options provided is:
4
Therefore, the answer is 4.
