Corundum vs. Topaz — What's the Difference?

Corundum is a crystalline form of aluminium oxide (Al2O3) typically containing traces of iron, titanium, vanadium and chromium. It is a rock-forming mineral.

Topaz ( TOH-paz) is a silicate mineral of aluminium and fluorine with the chemical formula Al2SiO4(F, OH)2. It is used as a gemstone in jewelry and other adornments.

An extremely hard mineral, aluminum oxide, Al2O3, sometimes containing iron, magnesia, or silica, that occurs in gem varieties such as ruby and sapphire and in a common black, brown, or blue form used chiefly in abrasives.

A precious stone, typically colourless, yellow, or pale blue, consisting of an aluminium silicate that contains fluorine.

(mineral) An extremely hard mineral, a form of aluminum oxide with the chemical formula Al₂O₃, that occurs in the form of the gemstones sapphire and ruby; it is used as an abrasive.

A large tropical American hummingbird with a yellowish throat and a long tail.

The mineral alumina (Al2O3), as found native in a crystalline state. Transparent varieties are used as gemstones, including sapphire, which is the fine blue variety; the oriental ruby, or red sapphire; the oriental amethyst, or purple sapphire; and adamantine spar, the hair-brown variety. It is the hardest substance found native, next to the diamond.

A colorless, blue, yellow, brown, or pink aluminum silicate mineral, often found in association with granitic rocks and valued as a gemstone.

Very hard mineral used as an abrasive

Any of various yellow gemstones, especially a yellow variety of sapphire or corundum.

A light yellow variety of quartz.

A silicate mineral of aluminium and fluorine, usually tinted by impurities.

An often clear, yellowish-brown gemstone cut from this.

A yellowish-brown color, like that of the gemstone.

A black Catholic soldier in the British Army.

Either of two species of very large hummingbirds in the genus Topaza.

A ruby-topaz hummingbird, Chrysolampis mosquitus, the male of which has bright ruby feathers on the head and topaz on the throat

Of a yellowish-brown color, like that of the gemstone.

A mineral occurring in rhombic prisms, generally yellowish and pellucid, also colorless, and of greenesh, bluish, or brownish shades. It sometimes occurs massive and opaque. It is a fluosilicate of alumina, and is used as a gem.

Either one of two species of large, brilliantly colored humming birds of the genus Topaza (Topaza pella or Topaza pyra), of South America and the West Indies.

A yellow quartz

A mineral (fluosilicate of aluminum) that occurs in crystals of various colors and is used as a gemstone

A light brown