Yes, diamond is a precious stone, which is defined by the online Free Dictionary as: "Any of several gems, including the diamond, emerald, ruby, and sapphire, that have high economic value because of...
Aquamarine, Tourmaline, Beryl, Garnet, Amber, Onyx, Moonstone, Peridot, Spinel, Zircon, Carnelian, Turquoise, Topaz, Agate, Lapis Lazuli, Jade, Chrysoberyl, Tanzanite, Emery, Opal and Amethyst. There...
Because they're beautiful and/or rare.
You tell me loser :P
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