Crystal Glass Tile What's The Difference Between Glass And Diamond And Crystal?

What's The Difference Between Glass And Diamond and Crystal? - crystal glass tile

I asked a shop just around the jewelry they have and what caught my attention is considered the model which is made of diamonds / crystals / glasses. I wonder how can I tell if a diamond, crystal or glass?
You need to have details of what the diamond, crystal and glass like or what kind of difference, they have!