Ok, so judging from the comments, you are asking if this is a variety of Quartz (not diamonds) and mentioned that glass is made of quartz…

So you are kinda right about glass being made of quartz. It’s the same mineral. However, what makes quartz, quartz is it’s crystalline structure, which you probably know is destroyed when it is smelted and turned into glass.

The crystalline structure is what gives quartz and durability, vs glass. Glass wears down like this, but quartz will wear down differently. You can make Quartz look similar to this by sandblasting it, but it’s not something that would happen naturally. I’m certain that this is glass.