- emerald
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/em"euhr euhld, em"reuhld/, n.1. a rare variety of beryl that is colored green by chromium and valued as a gem.4. Ornith. any of numerous small bright green hummingbirds of the genus Chlorostilbon.adj.5. having a clear, deep-green color.[1250-1300; ME emeraude, emeralde < AF, OF esmeraude, esmeralde, esmeragde < L smaragdus < Gk smáragdos; prob. ult. < Sem b-r-q shine ( > > Skt marak(a)la emerald)]
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Its physical properties are those of beryl. Its refractive and dispersive powers (i.e., its capacity to deflect light and to break white light into its component colours) are not high, so cut stones display little brilliancy or fire (flashes of colour). The colour that gives this gem its value is due to the presence of small amounts of chromium. The most important production of fine quality gem material is from Colombia; emeralds are also mined in Russia, Australia, South Africa, and Zimbabwe. Synthetic emeralds are identical to natural crystals and may rival them in colour and beauty.* * *
town, central Queensland, Australia, on the Nogoa River, at the junction of the Capricorn and Gregory highways, 172 miles (276 km) west of Rockhampton. P.F. MacDonald, an early settler, established Emerald Downs station (ranch) in the 1860s. In the 1880s the region's economy depended largely on gemstones, which still are exploited commercially and attract amateur gem collectors. Cattle and sheep raising, together with the cultivation of numerous crops (including cotton) irrigated with water from the Fairbairn Dam, are now the basis of the town's prosperity. Brisbane lies about 570 miles (917 km) to the southeast. Pop. (2006) local government area, 14,355.* * *
Universalium. 2010.