Some horses, especially older horses that are very relaxed, let their lower lip droop markedly. This is usually a normal finding. When these horses become more stimulated, the appearance changes. The key to this is that the appearance is symmetrical on left and right sides.
Because of corundum's hardness (pure corundum is defined to have 9.0 Mohs), it can scratch almost every other mineral. It is commonly used as an abrasive on everything from sandpaper to large machines used in machining metals, plastics, and wood.orundum from Brazil, size about 2 cm Ã 3 cm (0.8 in Ã 1 in). Corundum occurs as a mineral in mica schist, gneiss, and some marbles in metamorphic terranes. It also occurs in low silica igneous syenite and nepheline syenite intrusives.
In nature diamonds are rare, but not so in the gem world. Rubies and sapphires are different colored varieties of the mineral corundum. Now corundum is a fairly common mineral. Second only to diamond in hardness it has been mined extensively for abrasives.The emery on your emery boards and sand paper may contain corundum.hey are somewhat expensive, but readily available. The Carmen Lucia Ruby is an incredibly rare ruby due to both its size and quality. It is when you get into gems of a carat of more that they get really expensive. Good quality rubies in this size range are few and far between.