Question

Which rocks are too hard

Answer 1

Answer:

One type of quartz is easily identified by its hexagonal crystals, but quartz can also be found in a large mass. Quartz can be broken or weathered into the tiny pieces we know as sand. Quartz is a very hard mineral and in fact is the hardest of the common minerals. Quartz is number seven on the Mohs hardness scale.

Answer 2

I think obsidian is hard. If it's correct pls mark me brainliest