Determine the hardness of these minerals.
1. A mineral can scratch glass, but leaves behind a streak on the streak plate. What is the mineral’s hardness? (Hint 1: harness should be a whole number; Hint 2: the hardness of the mineral example in this question would be the value in between the number associated with scratching glass & leaving a streak on the streak plate)
2. What mineral on the Mohs scale has the same hardness? (Hint: see the Mohs scale on p. 2 of this handout, the answer is the mineral listed for the hardness you found in question 2.)
3. A mineral can be scratched by your fingernail. What is the mineral’s hardness?
4. What minerals on the Mohs scale have the same hardness?
5. A mineral is scratched by a wire nail, but not by a copper penny. What is the mineral’s hardness?
6. What mineral on the Mohs scale has the same hardness?