eli5: Why does sand which is a bunch of tiny rocks, turn into glass, but we can’t turn big rocks into glass?

Question

I’m very tired. Please help me understand this.

In: Other

Answer 1

What do you think sand is? It’s the result of those big rocks being crushed and abraded and sorted until what you have is rather pure quartz, because it’s much harder than the other minerals in the rock. We can do the same thing industrially, but there’s little point when there’s still plenty of glass-grade quartz left. Not to mention the huge amounts of waste that has no particularly productive use given the bulk.