The person,\nwho first saw the layered blue anatase, hardly believes in the natural origin\nof the stone. The voluminous rhombus, beautifully outlined by the transverse\nplanes of gentle pastel shades, gives the impression of a man-made product.<\/p>\n\n\n\n
However,\ncolorless (more precisely, almost colorless: the minimum color of the stone is\nstill present) is even more beautiful anatase. Even without being faceted, this\ngem sparkles and shimmers with all the colors of the rainbow, not surpassing,\nbut approaching in beauty to a diamond.<\/p>\n\n\n\n
Incidentally,\nit was the amazing optical properties of anatase that inspired scientists to\ncreate artificial jewelry – cubic zirconia – which is a synthetic analogue of a\nnatural mineral.<\/p>\n\n\n\n
Physical properties of anatase<\/strong><\/p>\n\n\n\n In the\nchemical aspect, anatase is titanium dioxide TiO2. Crystallization of oxidized\ntitanium under various conditions gives as many as three minerals – related to\neach other, but still different. The usual natural form of titanium oxide is\nrutile and brookite. Anatase, which differs from mineral counterparts in the\nform of crystals, is less common in deposits.<\/p>\n\n\n\n The\ndifference in the crystalline “packing” of atoms generally changes\nthe light transmission of a substance. This is why anatase happens to be blue,\nwhile rutile is reddish and brookite is brown.<\/p>\n\n\n\n The anatase\ncrystalform is the dipyramidal\noctahedron. Renee Just Gayui, who examined the stone in 1801, found such a form\nworthy of perpetuation, and gave the mineral a modern name.\n“Anatasis”, translated from ancient Greek, means “elongated,\noblong.”<\/p>\n\n\n\n Beautiful anatase is rare<\/strong><\/p>\n\n\n\n Among the\nmasters of the processing of semi-precious stone, it became customary to call\nanatase a stone of blue tones of varying degrees of transparency and\nuniformity. In mineralogical collections, crystals that are opaque to complete\nblackness and translucent anatases of cold greenish, as well as warm\nreddish-brown shades are used.<\/p>\n\n\n\n The natural\nsize of crystalline anatase usually does not exceed ten millimeters. Large\nspecimens of rhomboid anatase are especially valued by buyers. The smooth edges\nof the stone shine very much, but anatase crystals often have defects: cracks,\ninclusions, formation defects.<\/p>\n\n\n\n In the\nSwiss Alps, quite large anatases of a beautiful yellow tone are found. In\nPoland, near the border with the Czech Republic, anatases 5-6 cm in size are\nfound. Each mountainous country in the world boasts its own anatases – but\nalmost no anatases are suitable for jewelry processing.<\/p>\n\n\n\n Anataz: a stone far from jewelry quality<\/strong><\/p>\n\n\n\n Bright\nshine and pronounced dispersion are characteristic of transparent anatases. In\ndeposits, such stones are found in single quantities, and they are small in\nsize. Theoretically, after cutting from natural slightly colored anatase, an\ninsert of no more than one or two carats can be obtained.<\/p>\n\n\n\n Moreover! There are rumors in the jewelry environment that someone has personally seen faceted anatases of excellent quality weighing six carats – however, these legends do not find clear evidence. It is only known that anatase crystal suppliers of the best collection quality collect semiprecious stones in diamond placers of Yakutia and Brazil. Collectible – but not jewelry!<\/p>\n\n\n\n Beautifully colored dipyramidal (rhomboid) anatases become an expensive commodity. However, the attempts of amateur masters to adapt the frame and suspension to the stone end with the destruction of anatase.<\/p>\n\n\n\n