How Does Sand Become Glass?

“Like most peo­ple, I don’t usu­al­ly spend much time think­ing about sand or the glass-mak­ing process. Research­ing this book was a great oppor­tu­ni­ty to do just that. In the process, I learned all kinds of inter­est­ing things.

“Here’s my favorite fact: that par­rot­fish munch on coral to get at the tiny crea­tures inside. The coral breaks down in their diges­tive sys­tem, and brand new sand comes out ‘the oth­er end.’ We have par­rot­fish to thank for many of the world’s sandy beaches.”