Spinel facet polished collier

The mineralogy Spinel is understood by a group similar minerals, only some of which are of gem quality. The origin of the name is unclear, possibly of Greek or Latin for spark spina arrow. The color giving substances are iron, chromium, vanadium and cobalt. Large stones are rare, star spinels very rare. The structure of spinel consists of 32 oxygen atoms, and 24 cations. Eight of the cations have a four-encompassing went (tetrahedral positions), 16 have a six-encompassing went (octaëderposities). There are two structurally different types: the normal spinel structure, and the inverse spinel structure. In the normal spinel structure is the distribution of cations on tetrahedron and octahedron positions as follows: 8 in tetraëderposities + R2, R3 + 16 in octaëderposities. In the inverse spinel structure is the division: 8 R3 + in tetraëderposities, and 8 and 8 R3 + R2 + in octaëderposities. Spin Ellen have been used since ancient times along with other stones called carbuncles. The current name arose later. As can be seen in numerous jewelry spinel was formerly very popular. However, initially, for example, considered in the British crown jewels spinel as ruby. In the past, spinels mainly found in the gemstone deposits in Burma and Sri Lanka. Some displaying ones kattenoogeffect. Spinel is to distinguish the color of ruby difficult. Spin Ellen gem quality are found in Thailand, Cambodia and Laos. The sites in India and Australia are not as important. Spin Ellen are found in Africa, Madagascar and Kenya. Recently, also found spinels in Pakistan and Afghanistan. Spinel gem quality is also known from Brazil. In the United States, particularly in California, Montana, New York, New Jersey, North Carolina, and Virginia. In Canada came crystals to 5cm size of the marble Glancoe. Also in Ontario and Tajikistan come spinels for. Sometimes reach the pure rose colored cut stone weighing 100 carats. In 1986, a spinel is found with a weight of 5.1 kilograms. In Europe spinels found in Norway, Finland, Italy, and Germany. In Crown Jewels were many spinels used. The best known is probably the 398.5 carat heavy dark red spinel in the Russian imperial crown in the Arsenal in Moscow. The British state crown contains two large spinels, called the Black Prince Ruby of 170 carats and the Timur Ruby of 361 carats. St. Wenceslas Crown in Prague also contains large spinels, a total of 45 pieces. In the British Museum of London are two spinels 355- and 520 carats respectively.

Gemstone therapy Spinel (Dutch)