Opal Deposits outside Australia

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Jewellery pendant with Mexican opal

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Access by dirt-road; the area is a semi-aridclimate zone with numerous cactus plants.

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Miners entering the active mining area

Tunnel leading to the next underground opal deposit.

Miners inspecting some opal veins

Miner working on rock containing opal. The broken boulders are stacked in a pile to be broken down by hand into pieces 5 cm or less to improve recovery of gem-quality material.

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bb bbb bbbb bbbb b.Here the miner is hammering on a rock which was dynamited from the quarry wall. The opal is trapped in the before mentioned cavities completely but occasionally it is found as loose nodules in the open spaces. These loose nodules, which may be "as large as a hen's egg", are generally the highest quality material.

Pieces of rough Mexican opal

Spectacular carved piece of opal

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Several miners were still strolling around showing off their wares in typical glass vials. But most of the opal - as they said - was material for the "gringos": cheap fire opal.

Numerous pieces of rough fire opalSelection of carved Mexican opal

Carved fine Mexican opal Mexican opal in rhyolite

Interesting carved Mexican opal

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Superb pieces of Mexican opal

Black Fire Jelly

Very nice top quality Mexican opal cabochons. The rough for these pieces has been stored initially for five years before cutting. An opal dealer recently reported that they had problems with material coming from a shaft just 20 m from the original mine where the material used to be durable. The opals broke into pieces when polished.

Mexican opal in rhyolite

Precious Opals in Canada

• The Klinker Opal Deposit, located near Vernon, B.C.was discovered on October 14, 1991.

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clear amber to translucent /opaque white to dark brown and exhibiting a variable intensity "play of colour" in a flash to broad flash pattern.

http://www.canadianrockhound.com/winter99 993103/cr _opals.html

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What better way to spend a day than to try your luck at finding your own opals?

The Klinker Opal Property is located in the mountains approximately 40 kilometres by road from Vernon, BC and is situated at an elevation of about 1500 metres above sea level.

DIG YOUR OWN OPALS!

Capped boulder opal doublet pendant.

Natural solid semi-crystal opal pendant.

Black-backed DoubletsBoulder Opal Doublets

Opal from Okaganan Deposits, B.C.

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Exquisite stones as large as 315 carats have been cut

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United States

Most important area is in northern Nevada (Virgin Valley); opal here replaces petrified wood in volcanic ash. Has extremely high water content, get beautiful black opal with red flashes. Is notorious for dehydrating with time, however, causing cracking, crazing and making it less marketable.

Louisiana.--The reported precious opal from Louisiana is a sandstone/quartzite with precious opal cement and matrix. It has blue or purple play of color. The material could be cut into cabochons for jewelry and other items of interest. To date, most of the material has been cut into large (over 2-inches in diameter) gemstone spheres.

Nevada.--Nevada is known for precious opal from Virgin Valley. The first discovery of precious opal in the Virgin Valley area was in 1905 or 1906. Since then a significant quantity of the highly prized opal has been recovered. Virgin Valley opal is comparable to any in the world for its vivid play of color and in terms of the size of material available.

Opal from Royal Peacock mine, Virgin Valley, Nevada. http://www.royalpeacock.com/

Hondourus VAR: opalitic sandstoneHondourus

Location : Lempira-Gracios a DiosHost rock : Basalts and trachytesProduction : Commercial-minor

Location : PiauiHost rock : Sandstone, underlain by dolerite.Production : Commercial-minor

Brazil

Gem & Gemmology, Summer 1 9 9 6 : Opal from Shewa Province, Ethiopia

Ethiopia