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This is a list of prices of chemical elements. Listed here are mainly average market prices for bulk trade of commodities. Listed here are mainly average market prices for bulk trade of commodities. Data on elements' abundance in Earth's crust is added for comparison.
Biogenic silica (bSi), also referred to as opal, biogenic opal, or amorphous opaline silica, forms one of the most widespread biogenic minerals. For example, microscopic particles of silica called phytoliths can be found in grasses and other plants. Silica is an amorphous metalloid oxide formed by complex inorganic polymerization processes.
It's valued at over $1 million and was purchased by the South Australian Museum in Adelaide which will be presenting it as part of their "Opals" exhibit to celebrate 100 years of gemstone mining ...
Opalite is a trade name for synthetic opalescent glass and various opal and moonstone simulants. Other names for this glass product include argenon, sea opal, opal moonstone, and other similar names. [1] [2] It is also used to promote impure varieties of variously colored common opal. [1]
The Halley's Comet Opal is a very fine specimen, with few flaws or blemishes and a large green and orange 1.6 cm (0.63 in) thick color bar which goes through the opal. Formed about 20 million years ago, it is an example of a nobby, which is a natural lump-shaped opal found only at Lightning Ridge. [2] As of 2006 it was for sale at $1.2 million. [3]
It is the largest and one of the most valuable opals mined to date, consisting of 99 per cent gem opal (the other 1 per cent being soil). The Olympic Australis measures 11 inches in length, 4 + 3 ⁄ 4 inches height, 4 + 1 ⁄ 2 inches in width, and weighs 17,000 carats (3,450 g, 121.7 oz, or 7.6 lb).
The opal is just under 5,000 carats; roughly equivalent in size to two cricket balls. [1] Although rough-cut, it is polished on two sides. [3]Due to the evaporation of an inland sea several million years ago, South Australia is one of the few places on Earth where opals of this size can be created.
The Olympic Australis opal is the largest and most valuable opal yet found (as of 1961) [1] and was valued at A$2,500,000 in 1997. [2] It was found in 1956 at the 'Eight Mile' opal field near the town of Coober Pedy in South Australia. [3] The opal was found at a depth of 9.1 metres (30 ft).