LARGE crystals of corundum have been grown for many years by the flame-fusion process originated by Verneuil 1. Crystals coloured by small amounts of chromium, titanium, vanadium and other ...
Glittering blue sapphires, so suggestive of piercing cold, have remarkably hot origins deep beneath the surface. For years, sapphires been turned up in volcanic deposits such as the Volcanic Eifel, ...
Sapphire is September's birthstone. This gem belongs to the corundum family. Corundum is inherently colorless, according to the International Gem Society. So, each stone's elemental structure ...
Rubies are formed of a mineral called corundum, comprised of aluminum oxide. The red color is caused by traces of chromium. Corundum also forms sapphire in many colors, which generally come from ...
Aluminum oxide (Al2O3), also known as alumina, corundum, sapphire, or ruby, is one of the best insulators used in a wide range of applications: in electronic components, as a support material for ...
Like their gemstone cousin the sapphire, rubies are just a variety of corundum, or aluminum oxide. Where sapphire gets its blue tint mainly from iron, rubies get their pink to blood-red hue from ...
Aluminum oxide (Al2O3), also known as alumina, corundum, sapphire, or ruby, is one of the best insulators used in a wide range of applications: in electronic components, as a support material for ...