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Langgan was a qīng 青 "green; blue; greenish black" (see Blue–green distinction in language) gemstone of lustrous appearance mentioned in numerous classical texts. They listed it among historical imperial tribute products presented from the far western regions of China, and as the mineral-fruit of the legendary langgan trees of immortality ...
Though white schiller is the most common, in rarer specimens, orange or blue lusters are produced. [2] This effect is most typically produced by adularia, a K-feldspar or orthoclase (KAlSi 3 O 8), from which the name is derived. [3] [4] [5] Adularescence appears in numerous other gemstones, notably common opal, rose quartz and agate. However ...
Asterism on the surface of a blue star sapphire. A purple-pink star sapphire displaying asterism in a platinum ring.. An asterism (from Ancient Greek ἀστήρ (astḗr) 'star' and -ism) is a star-shaped concentration of light reflected or refracted from a gemstone.
Download QR code; Print/export ... This is a list of gemstones, organized by species and types. Minerals ... Mobile view ...
Originating from the Persian word for the gem, lāžward, [1] lapis lazuli is a rock composed primarily of the minerals lazurite, pyrite and calcite. As early as the 7th millennium BC , lapis lazuli was mined in the Sar-i Sang mines, [ 2 ] in Shortugai , and in other mines in Badakhshan province in modern northeast Afghanistan . [ 3 ]
A recently discovered gemstone, blue ominelite, is the Fe-analogue (Fe, Mg) to grandidierite (Mg, Fe). [5] Grandidierites display strong trichroic pleochroism. That means that it can show three different colors depending on the viewing angle: dark blue-green, colorless (sometimes a very light yellow), or dark green.
A clear variety found in Brazil and Sri-Lanka can be cut into a gemstone. [11] Faceted andalusite stones give a play of red, green, and yellow colors that resembles a muted form of iridescence , although the colors are actually the result of unusually strong pleochroism .
Aquamarine is blue with hues of green, caused by trace amounts of iron found within the crystal structure. It can vary from pale to vibrant and transparent to translucent. Better transparency in aquamarine gemstones means that light may go through the crystal with less interference. The hexagonal crystal system is where aquamarine crystallizes.