Mohs Mineral Hardness Scale Set, with (9) Specimens, Magnifier and Accessories. Multiple Minerals We've got rocks by the box. You pays yer money and you gets our gallimaufry of geological goodies. The Mohs Kit is a mineral hardness scale set, with (9) specimens: gypsum, talc, calcite, fluorite, apatite, orthoclase, quartz, topaz and corundum. Includes a small magnifier, nail, ceramic streak plate, tray and an instruction pamphlet.