This is the traditional scale of hardness collection and a test kit. Samples include Talc, Gypsum, Calcite, Fluorite, Apatite-Triphylite, Feldspar, Quartz, Beryl-Topaz and Corundum. Test kit includes white streak plate, penny, glass plate and nail. Specimens are 1" x 1-1/2" and number coded to match enclosed ID list in included Information Sheet.
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