Corundum Mineral – Pack of 2
by American Educational Products

Corundum is the crystalline form of aluminum oxide, and traces of iron, titanium, vanadium and chromium can be found within it. It is typically colorless, but different impurities will give Corundum a different color. The transparent specimens of this mineral find use as gems, with red stones being called ruby, and pink-orange referred to as padparadscha. Any other colors are referred to simply by adding “sapphire” after their color. For example, a green piece of Corundum would be called “green sapphire”.

Because of its hardness of 9.0 Mohs when in its purest form, it is capable of scratching almost all other minerals. If finds common use as an abrasive, from sandpaper to machining. It also has a density of 4.02g/cm³, which is usually high for not just a transparent mineral, but one that has been formed from low atomic mass elements such as aluminum and oxygen.

Each rock or mineral specimen measures approximately 1-2 inches in length along its longest side.

Origin: Madagascar