Which type of glass is crystal?

I dropped a crystal glass which shattered all over the kitchen floor. The interesting part of it was there were no shards it turned into tiny little cubes. Like a shattered car window

You can tell if it's the real deal if it turns purple when exposed to sunlight for some time. We have a garden window full of it.

Numerous studies have shown that storing various beverages in lead crystal decanters results in the leaching of lead into the liquid. Not ideal.

The optical density, refractive index, is greater than most glass: giving it the colours.

Player dlb, True. We have five crystal decanters and they're don't change colours as my husband. keeps his drinks in them.

Uninitialized, not if an acidic substance is stored in it.