A mineral occuring in octahedrons of great hardness and various colors, as red, green, blue, brown, and black, the red variety being the gem spinel ruby. It consist essentially of alumina and magnesia, but commonly contains iron and sometimes also chromium.
A hard, glassy mineral occurring in many various attractive colors: red, rose, orange, brown, pink, yellow, blue, violet, purple, mauve, green, and black. Completely colorless (white) spinel is rare. Some years ago, synthetic white spinel was used in costume jewelry as a diamond substitute. Although natural spinel is quite hard, the synthetic spinels were not very hard, so spinel developed an undeserved reputation as a low-quality stone.
Spinel is the classification of a large group of related minerals that has a small group of gemstone quality stones. Spinel exhibits a wide range of colors including red, pink, orange, yellow, brown, blue, violet, purple, green and black. On Mohs’ scale of hardness, spinel is 8. Sources include Burma (Myanmar), Cambodia, Sri Lanka, Afghanistan, Australia, Brazil, Madagascar, Nepal, Nigeria, Tadzhikistan, Tanzania, Thailand and the United States (New Jersey). (See Spinel Facts.) (Note: Sources listed in order of primary and secondary deposits.)
a hard glassy mineral consisting of an oxide of magnesium and aluminum; occurs in various colors that are used as gemstones
a beautiful and little known gemstone which occurs in many colors
a particular type of crystalline metal oxide structure in which a portion of the basic metal in the crystalline lattice is replaced by a different (second) metal
crystalline structure of oxides in which the oxygen ions roughly form a compact face-centred cubic assembly and where the cations occupy octahedral and tetrahedral sites of these assemblies
Is often mistaken for Ruby and it was only recently, around 1900, moved out from under the Ruby moniker and given it's own classification and identified separately from Ruby. The most famous Spinel is probably in the British Crown Jewels as un until around the 1940's that huge Spinel was always considered a Ruby. Spinel ranges in color from red to black to yellow
A gemstone found in a variety of colors; the most valuable resembles ruby red.
magnesium aluminium oxide, may mean "spark" in Greek.
a hard gemstone appearing in a variety of colors from the valuable red, such as the so-called Black Princeâ€(tm)s ruby, through to blue and green. Popular in medieval jewelry.
a mafic rock without plagioclase and peridotite containing spinel, a (magnesium-iron) aluminum silicate material.
MgAl. An accessory mineral in some igneous rocks.
(spih-NEL) A transparent stone that varies in color and may appear in ruby-red, purple, sapphire-blue, black or orange. Spinel rates an 8 on the Mohs hardness scale.
A natural gemstone which occurs in many colours. Synthetic white spinel was often used in the past as a diamond substitute.
A vibrant, cobalt blue semi-precious stone that is found in Sri Lanka, Thailand, Afghanistan and Russia.
Spinel is a very hard semi-precious stone ranging in color from red to black to yellow, frequently resembling rubies. Spinel is found in Burma, Sri Lanka and Thailand. Spinel has a hardness of 8.
Spinel is a very hard semi-precious stone composed of octahedral crystals. Spinel ranges in color from red to black to yellow, frequently resembling rubies. Iron and chrome are components of spinel, giving it its color. Spinel belongs to the feldspar species and is found in Burma, Sri Lanka and Thailand.
A mineral which resembles corundum, especially red spinel which has been mistaken for a ruby.
Probably named from the Latin word "spina", (meaning "thorn"), for its pointed crystals, spinel is a hard mineral with octahedral crystals occurring in igneous and carbonate rocks. It consists essentially of alumina and magnesia, but commonly contains iron and sometimes also chromium. It is found in a variety of colors including blue, green, brown, black, and the valuable red variety which resembles a ruby. It was popular in medieval jewelry.
A gemstone found in a wide range of colors, the most valuable resembling ruby red.
any of a group of very ahrd minerals consisting chiefly of oxides of magnesium and aluminum and occurring in various colors. The magnesium may be replaced in part by ferrous iron, zinc, or manganese, and the aluminum by ferric iron or chromium. [AHDOS
The spinels are any of a class of minerals which crystallize in the isometric system with an octahedral habit. The general formula is as (X)(Y)2O4, with X representing cations occupying tetrahedral sites and Y cations occupying octahedral sites. Divalent, trivalent, and quadrivalent cations can occupy the X and Y sites, and they include magnesium, zinc, iron, manganese, aluminium, chromium, titanium, and silicon.