Accidental Exposure. Sometimes women take medication before they realize that they are pregnant. When this happens, they may worry about the effects of the medication on their unborn baby. The first thing a woman who is pregnant or who is planning on becoming pregnant should do is talk with her healthcare provider.
Corundum is found as a primary mineral in igneous rocks such as syenite, nepheline syenite, and pegmatite. Some of the world's most important ruby and sapphire deposits are found where the gems have weathered from basalt flows and are now found in the downslope soils and sediments.
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.