I remember being told, back in the day, on the various channels that belong(ed) to Steve, that ALL gemstones are rare. Except: Csarite, Nilimani, Conch Shell, that VERY rare stone that comes in shades of green. I may be wrong, but I 'think' it's called Jade, but I may be wrong. Something that comes from a mine in Australia: again, not sure, but I think the mine is called Argyle. Ooo, and the Parti Sapphires, anything from Songea, Opals, Spinel: of a variety of shades. And of course, Tanzanite: now in a variety of shades. Probably more. BUT, don't forget ALL gemstones are rare