Can you turn glass back into sand? - BBC Science Focus ...
2017-7-19 · Technically, natural sand is made of quartz crystals of silicon dioxide, whereas glass is the non-crystalline, amorphous form of silicon dioxide. But when it is ground down enough, the difference isn’t obvious. Crushed glass is sold as an alternative to sand for pool filters – in fact, recycled crushed glass has been considered as a partial ...