Smooth white stones can make a dye, as can smooth black and rough white and white, yellow-veined ones.
The smooth black one is the only one out of the shebang that can be turned into jewelry with only the stone as an ingredient, to my knowledge. The rough black stone can be used for sling bullets, I believe (but, technically, can't most stones be turned into bullets?)? I remember it has a use somewhere but I can't remember what use. Either way, its definitely an item that finds its way into jewelry material bins but never into jewelry pieces themselves.