Aquamarine, beryl

Scandium is apparently much more abundant (the 23rd most) in the sun and certain stars than on earth (the 50th most abundant). It is widely distributed on earth, occurring in very minute quantities in over 800 mineral species. The blue color of beryl (aquamarine variety) is said to be due to scandium. It occurs as a principal component in the rare mineral thortveihte, found in Scandinavia and Malagasy. It is also found in the residues remaining after the extrachon of tungsten from Zinnwald wolframite, and in wiikite and bazzite. 

Beryl Aquamarine, emerald BesA SiOs) All colors, 2.70-2.82 1.580-1.575 7.5-8 Poor cleavage perpendi-... 

R.R. Viana, G.M. da Costa, E. De Grave, H. Jordt-Evangelista, W.B. Stem, Characterization of beryl (aquamarine variety) by Mossbauer spectroscopy. Phys. Chem. Miner. 29, 78-86 (2002)... 

Beryllium is found in some 30 mineral species, the most important of which are bertrandite, beryl, chrysoberyl, and phenacite. Aquamarine and emerald are precious forms of beryl. Beryl and bertrandite are the most important commercial sources of the element and its compounds. Most of the metal is now prepared by reducing beryllium fluoride with magnesium metal. Beryllium metal did not become readily available to industry until 1957. 

Beryl. Beryl [1302-52-9] Be Al Si O g, is called aquamarine [1327-51 -1] when pale green or blue from inclusion of Fe emerald [12415-33-7] when dark green from Cr or at times V, and morganite or red beryl when pink or red, respectively, from Mn. Only the synthetic emerald is in commercial production, although the other colors can also be grown. Both the flux and hydrothermal techniques are used to grow this luxury synthetic. 

Colored beryl gems, for example, aquamarine, are highly sought-after... 

A colorless mineral known as corundum (composed of aluminum oxide) is colorless. A red variety of corundum known as ruby, a precious stone, owes its color to impurities of chromium within the crystal structure of corundum. Blue and violet varieties of corundum are classified as sapphires, the blue being the result of iron and titanium impurities, and the violet of vanadium impurities within the corundum crystal structure. Another colorless mineral is beryl (composed of beryllium aluminum silicate) but blue aquamarine, green emerald, and pink morganite, are precious varieties of beryl including different impurities aquamarine includes iron, emerald chromium and vanadium, and morganite manganese. 

French chemist Louis-Nicolas Vauquelin Rare alkaline-earth metal derived from the mineral beryl of which emeralds and aquamarines are crystals. 

Gem quality beryls are aquamarine (blue), emerald (green), and golden beryl. Likewise, amethyst b a violet-colored silica, and sapphire (blue) and ruby (red) are alumina. Yet pure beryl (Be,AI>Si lO ). alica (SiO ). and alumina (AI O>) are colorless. Explain... 

Aquamarine, like emerald, is a transparent variety of beryl, or beryllium silicate. Its light blue to blue-green color results from small amounts of iron in the crystal. Like most beryl stones, it measures 7.5 to 8 on the Mohs hardness scale. Most aquamarine gemstones come from Brazil. 

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