a translucent mineral consisting of hydrated silica of variable color; some varieties are used as gemstones
A mineral consisting, like quartz, of silica, but inferior to quartz in hardness and specific gravity, of the chemical formula SiOu00B7nHO.
, , A colloquial name used in molecular biology referring to a particular stop codon sequence, "UGA."
from the precious stone, invented in the nineteenth century.
A type of petrol made by British Petroleum designed to be unable to be used for petrol sniffing.
Opal is a hydrated amorphous form of silica; its water content may range from 3% to 21% by weight, but is usually between 6% to 10%. Because of its amorphous character it is classed as a mineraloid, unlike the other crystalline forms of silica which are classed as minerals. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone, rhyolite, marl and basalt. Opal is the national gemstone of Australia, which produces 97% of the world's supply. This includes the production of the state of South Australia, which amounts to around 80% of the world's supply. The internal structure of precious opal makes it diffract light; depending on the conditions in which it formed it can take on many colors. Precious opal ranges from clear through white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, and black. Of these hues, the reds against black are the most rare, whereas white and greens are the most common. It varies in optical density from opaque to semi-transparent. For gemstone use, its natural color is often enhanced by placing thin layers of opal on a darker underlying stone, like basalt. Common opal, called "potch" by miners, does not show the display of color exhibited in precious opal.
Chambers 20th Century Dictionary
ō′pal, n. a precious stone of a milky hue, remarkable for its changing colours.—n. Opalesc′ence.—adjs. Opalesc′ent, reflecting a milky or pearly light from the interior; O′paline, relating to, or like, opal.—v.t. O′palise. [Fr. opale—L. opalus.]
The Nuttall Encyclopedia
a variety of quartz, of which the finest kind, precious opal, is translucent, with blue or yellow tint, and when polished with a convex surface shows an admirable play of colours; it is found chiefly at Cerwenitza, Austria.
The numerical value of opal in Chaldean Numerology is: 1
The numerical value of opal in Pythagorean Numerology is: 8
Sample Sentences & Example Usage
The Opal dossier is being currently examined and there were some additional questions raised by the Commission, whether we are ready to take a decision or not depends on the completeness of the answers.
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Translations for opal
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