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According to a popular but controversial story, alexandrite was discovered by the Finnish mineralogist Nils Gustaf Nordenskiöld (1792–1866), and named alexandrite in honor of the future Emperor of All Russia Alexander II Romanov. Nordenskiöld's initial discovery occurred as a result of an examination of a newly found mineral sample he had ...
Gadolinite; Gahnite; Gahnospinel; Garnet group: Pyralspite. Almandine; Pyrope; Spessartine; Ugrandite. Andradite. Demantoid; Melanite; Topazolite; Grossular ...
Synthetic alexandrite is an artificially grown crystalline variety of chrysoberyl, composed of beryllium aluminum oxide (BeAl 2 O 4). The name is also often used erroneously to describe synthetically-grown corundum that simulates the appearance of alexandrite , but with a different mineral composition.
Note: René Haüy discovered that emeralds and beryls crystals are geometrically identical. He asked Vauquelin for a chemical analysis, and so Vauquelin found a new "earth" (beryllium oxide). Carl Wilhelm Scheele (1742 –1786), discovery of oxygen with Priestley; identification of molybdenum, tungsten, barium, hydrogen, and chlorine.
Emerald of Saint Louis, [5] 51.60 carats cut; discovered in Austria, probably Habachtal, resides in the National Museum of Natural History, Paris Gachalá Emerald [ 6 ] Mogul Mughal Emerald , 217.80 carats cut; mined in Colombia and cut in the Mughal empire in Hijri year 1107 (1695–1696), resides in the Museum of Islamic Art, Doha , Qatar [ 7 ...
The Alexandrite effect has also been observed in some other minerals, such as fluorite, sapphire, kyanite, monazite, spinel, garnet, tourmaline, and rare-earth oxalates. Not to be confused with the alexandrite effect, some minerals also exhibit pleochroism. The former is a response to different wavelengths of light in general, the latter an ...
Main emerald producing countries. Emerald is a gemstone and a variety of the mineral beryl (Be 3 Al 2 (SiO 3) 6) colored green by trace amounts of chromium or sometimes vanadium. [2] ...
Circa 1985, Roy Whetstine claimed to have bought the 1905-ct stone for $10 at the Tucson gem show, but a reporter discovered that L.A. Ward of Fallbrook, California, who appraised it at the price of $1200/ct, had appraised another stone of the exact same weight several years before Whetstine claimed to have found it.