The scientific name of a sapphire crystal is called Corundum. A sapphire (corundum) is an aluminum oxide mineral (Al2O3). Its crystal structure is hexagonal. Corundum (sapphires) comes in all color types.
What gemstones are corundum?
Corundum has two primary gem varieties: ruby and sapphire. Rubies are red due to the presence of chromium, and sapphires exhibit a range of colors depending on what transition metal is present. A rare type of sapphire, padparadscha sapphire, is pink-orange.
Is Blue corundum sapphire?
Sapphire is one of the two gem-varieties of corundum, the other being ruby (defined as corundum in a shade of red). Although blue is the best-known sapphire color, they occur in other colors, including gray and black, and they can be colorless. A pinkish orange variety of sapphire is called padparadscha.
What gem family is sapphire?
Corundum is a mineral species that includes two world’s most precious gemstones, ruby and sapphire.
Is Emerald a corundum?
The three other types of precious stones – rubies, sapphires and emeralds – are all referred to as “colored stones”. Scientifically speaking, rubies and sapphires are the same mineral (corundum). … As for emeralds, they are made of beryllium (beryls).
Is topaz a corundum?
As nouns the difference between corundum and topaz
is that corundum is (mineral) an extremely hard mineral, a form of aluminum oxide with the chemical formula al]]2[[oxygen|o3, that occurs in the form of the gemstones sapphire and ruby; it is used as an abrasive while topaz is a clear, yellowish-brown gemstone.
How rare is corundum?
Ranking a 9 on the Mohs scale of hardness (diamond is a 10), corundum has been mined extensively for abrasives. The emery on your emery boards and sand paper may contain corundum. Gem-quality corundum is quite a bit rarer, consisting of only a percent or so of all the corundum found.
Is corundum a gemstone?
The corundum family of gemstones consists of ruby and sapphire. Corundum is very compact, dense, and lacks gemstone cleavage. It’s also the second hardest natural mineral after diamond. … All other colors of corundum, including colorless, are called sapphires.
What is corundum used for?
In addition to its use as a precious gem, corundum finds some use as an abrasive, owing to the extreme hardness of the material (9 on the Mohs hardness scale). It is used for grinding optical glass and for polishing metals and has also been made into sandpapers and grinding wheels.
What is the rarest sapphire color?
The rarest sapphire is the Padparadscha, an extremely rare pink and orange stone that is stunning to behold. However, the most valuable sapphires are the Kashmir variants, which are blue.
What is corundum stone?
Corundum is an aluminum oxide that commonly forms hexagonal barrel-shaped prisms that taper at both ends or as thin tabular hexagonal plates. It has a hardness of 9 on the Mohs scale, making it one of the most durable commercial gemstones. It has no dominant cleavage and fractures in a conchoidal manner.
What is Star corundum?
A variety of Corundum. A variety of corundum exhibiting a star pattern when viewed down the C axis. The chatoyance is due to oriented microscopic inclusions.
Is corundum a mineral or a rock?
Corundum is the second hardest natural mineral known to science (1/4 the hardness of diamond). Gem varieties are sapphire and ruby. Corundum may occur on a large scale in some pegmatites. It is also found in silica-poor hornfelses (a contact metamorphic rock).