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opal
opal
opal Hydrous silica SiO
2.
nH
2O associated with the chalcedonic (see
CHALCEDONY) varieties of silica. A layer of water molecules trapped near the mineral surface causes the
iridescence (
opalescence) which is a diagnostic property of opal; sp. gr. 1.99–2.25;
hardness 5.5–6.5; amorphous; colourless, or milky-white to grey, red, brown, blue, green, to nearly black; resinous
lustre; normally
massive, but can be stalactitic,
botryoidal, and also in veinlets, the various varieties depending on the amount of water contained in the mineral, which can vary from 6% to 10%; no
cleavage;
conchoidal fracture; normally deposited at low temperatures from silica-bearing waters, and occurs as fissure fillings in rocks of any kind, and especially near geysers and hot springs. The variety known as precious opal has a milky-white or sometimes black body colour which exhibits a brilliant play of colours, usually blues, reds, and yellows. The colours can often disappear with the loss of water when the mineral is exposed to air.
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Opal-RT Technologies Announces Major European Expansion.
PR Newswire; 9/2/2009; 700+ words
; Opal-RT Europe to manage all European company operations and provide...customers and distributors MONTREAL, Sept. 2 /PRNewswire/ -- Opal-RT Technologies Inc. (http://www.opal-rt.com/), the leading developer of open, PC-based...
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Opal-RT Technologies Introduces SignalWire; Next-generation serial data link provides the flexibility of IEEE 1394 with three times the performance.
PR Newswire; 3/8/2004; 700+ words
; DETROIT, March 8 /PRNewswire/ -- Opal-RT Technologies Inc. (http://www.opal-rt.com/ ), the world leader in distributed...real-time processors. A standard feature of the Opal-RT FPGA product family (See press release...
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Opal Telecom, a winning jewel in Carphone's Crown; Opal Telecom wins a Queen's Award 2004 for Enterprise: Innovation.
M2 Presswire; 4/21/2004; 700+ words
; M2 PRESSWIRE-21 April 2004-Opal Telecom: Opal Telecom, a winning jewel in Carphone's Crown; Opal Telecom wins a Queen's Award 2004 for Enterprise: Innovation(C)1994-2004 M2 COMMUNICATIONS LTD RDATE:04202004 Opal Telecom, a jewel...
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Opal: The Phenomenal Gemstone.(Book review)
Magazine article from: The Mineralogical Record; 5/1/2007; ; 700+ words
; Opal: The Phenomenal Gemstone Edited by Janet...on-blackness appearance, this time of Opal: The Phenomenal Gemstone, No. 10 in the...published just a few months after No. 9. Opal places its major emphasis on rare "precious...
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Opal-RT Technologies Announces 'Real-Time 2008' - The 1st Annual Opal-RT International Users Conference.
PR Newswire; 3/4/2008; 700+ words
; MONTREAL, March 4 /PRNewswire/ -- Opal-RT Technologies today announced that...hosting "Real Time 2008" -- the 1st Annual Opal-RT International Users Conference, on...to provide a forum that brings together Opal-RT management and development teams...
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Opal Telecom chooses Wishstream for electronic bill presentment and payment; Opal Telecom, the leading public telephone operator, is to offer electronic bill presentment and payment services to its customers by adopting Wishstream's hosted solution, eStreamBill.
M2 Presswire; 7/24/2001; 700+ words
; M2 PRESSWIRE-24 July 2001-Opal Telecom: Opal Telecom chooses Wishstream for electronic bill presentment and payment; Opal Telecom, the leading public telephone operator, is to offer electronic bill presentment and payment services to its...
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Australian opal resources: outback spectral fire.
Magazine article from: Rocks & Minerals; 3/1/2007; ; 700+ words
; ...supplies more than 95 percent of the world's precious opal. Virtually all of this opal occurs in the Great Australian Basin (GAB), which...kilometres. Each Australian state where precious opal is mined typically produces opal that is considered...
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Opals set to shine with new grading technology.
M2 Presswire; 8/31/2009; 700+ words
; ...consortium of Australian Opal miners (Opal Producers Australia Limited...automated device to grade opals using image analysis...showing proportions of the opal's colours. A database...information on the GDA graded opals will allow participating...
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Opal: The Phenomenal Gemstone
Magazine article from: Mineralogical Record; 5/1/2007; ; 700+ words
; Opal: The Phenomenal Gemstone Edited hy J(UiCl CHffoni. Paul...9. O]inl places its major emphasis on rare "precious" opal as opposed to the common "potch" variety. Opal is actually a mineraloifi, defined as an inorganic natural...
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Opal Launches New Market-Leading Ethernet Proposition; New Flexible Working Legislation Set to Fuel Demand; Thousands of businesses 'unprepared' for changes.
M2 Presswire; 6/1/2009; 700+ words
; M2 PRESSWIRE-1 June 2009-OPAL: Opal Launches New Market-Leading Ethernet Proposition; New Flexible...for changes(C)1994-2009 M2 COMMUNICATIONS RDATE:01062009 Opal, the communications technology consultant and leading UKprovider...
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Whiteley, Opal
Encyclopedia entry from: Encyclopedia of World Biography
Opal Whiteley The life of American author Opal Whiteley (1897 – 1992) was a tragic one, shrouded...no mystery at all: her nature diaries, titled The Story of Opal , reached bestseller lists when they were published in 1920...
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opal
Book article from: The Columbia Encyclopedia, Sixth Edition
opal , a mineral consisting of poorly crystalline...but usually ranges from 3% to 10%. Common opal is usually colorless or white, but it may...color is due to fine-grained impurities. Opal is formed at low temperatures from silica...
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Opal
Encyclopedia entry from: Encyclopedia of Occultism and Parapsychology
Opal Gemstone of quartz or silica...name poederos, applied to the opal, refers to the complexion of youth. The superstition that opals were unlucky seems to have been...1829). The story claims the opal worn by Baroness Hermione of...
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Nanotechnology
Book article from: Space Sciences
...would save the mission. Early Attempts: OPAL Thanks to the miniaturization of off...built a satellite "mothership" called OPAL (Orbiting Picosatellite Automatic Launcher...microelectromechanical systems (MEMS) technology. OPAL was launched onboard a JAWsat launch vehicle...
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gemstones
Book article from: The Oxford Companion to the Earth
...attractive sheen, as in diamond and precious opal. The dispersion or ‘fire...inside the stone (Fig. 1). In precious opal, the minute spheres of silica which make...Slovakia) were the main source of precious opal (hydrated silicon dioxide) from Roman...
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