"Nature's Fireworks" - A Beginner's Guide to OPAL - Part 3 Australian Opal Fields

Written by Stuart Bazga


All ofrepparttar significant opal deposits in Australia duringrepparttar 145289 last 100 years are located within or surroundingrepparttar 145290 Great Artesian Basin. The most important deposits are found in New South Wales, South Australia and Queensland.

Today, mining is carried out atrepparttar 145291 following main areas and each area produces solid opal with specific characteristics and colour patterns.

Lightning Ridge, New South Wales

This is a town famous for its rich and rare black opal. Black opal gets its name fromrepparttar 145292 colour ofrepparttar 145293 “nobbies” or pieces of rough opal in whichrepparttar 145294 gems are usually found.

Black opal was first discovered here inrepparttar 145295 late 1880’s, however its commercial value was not at first recognised by buyers. It wasn’t untilrepparttar 145296 early 1900’s that some opal nobbies were found and shafts dug.

Opal occurs either as “nobbies” or in seams and thin layers within a soft greyish clay stone. The opal dirt levels occur between six and eighteen metres fromrepparttar 145297 surface, but have been found at depths as deep as thirty metres. The fields also yield opalised shells, wood and reptilian bones.

Some ofrepparttar 145298 traditional fields around Lightning Ridge includerepparttar 145299 Three Mile and Thorleys Six Mile.

White Cliffs, New South Wales

Located 295 kilometres northeast of Broken Hill, White Cliffs is Australia’s oldest opal field, where mining began about 1889. As with most towns with mining operations,repparttar 145300 population quickly soared, peaking at 5,000 in its heyday.

The light crystal opal found at White Cliff quickly became famous onrepparttar 145301 world market. The opal fields producedrepparttar 145302 first commercially accepted opal, far surpassingrepparttar 145303 quality ofrepparttar 145304 Hungarian mines, as opal displaying such vivid colours had never been seen before.

Between 1903 and 1914,repparttar 145305 richer areas ofrepparttar 145306 opal field became exhausted and a decline in production resulted. The effects of World War 1 also affectedrepparttar 145307 area, contributing torepparttar 145308 decline.

Central Queensland

The history of opal in Queensland dates back torepparttar 145309 early 1870’s, but it wasn’t until 1889 whenrepparttar 145310 gem was successfully marketed. The real development ofrepparttar 145311 vast opal deposits began in 1873 withrepparttar 145312 discovery of fine quality opal north of Thargomindah.

During those early years production was low as there was no ready market forrepparttar 145313 gem. It tookrepparttar 145314 efforts and determination of an entrepreneur named Tully Woolaston to establishrepparttar 145315 industry.

"Nature's Fireworks" - A Beginner's Guide to OPAL - Part 2 World Deposits

Written by Stuart Bazga


Althoughrepparttar largest opal fields are in Australia, opal is also found throughoutrepparttar 145288 world from Europe torepparttar 145289 South Americas, North America and South East Asia. It has been mined in Brazil, Honduras, Indonesia, Mexico, Hungary, western parts ofrepparttar 145290 USA and more recently Canada.

Following is a synopsis ofrepparttar 145291 countries where opal is currently mined:

Mexico:

The Mexican opal fields are primarily located inrepparttar 145292 Queretare and Jalica regions. These regions have been known to be producing opal sincerepparttar 145293 time ofrepparttar 145294 Aztecs, andrepparttar 145295 opal is commonly referred to as “Fire Opal.” The colouration ofrepparttar 145296 Mexican opal ranges from bright red to orange and arerepparttar 145297 only ones faceted rather than left as cabochons.

Canada:

Since 1973 opal has been mined in British Colombia, with gem quality opal being discovered atrepparttar 145298 Klinker, Queen and Eagle Creek mines inrepparttar 145299 1990’s. Precious opal from Klinker is found to have excellent brightness and multicolour flash. Bothrepparttar 145300 Queen and Eagle Creek mines contain occurrences of transparent, translucent or opaque deposits of common opal.

United States of America:

Idaho

Opal mining isrepparttar 145301 second largest contribution torepparttar 145302 total out put of gem production inrepparttar 145303 state. Varieties of opal being mined include precious, which comes in a varity of colours (white and pink, yellow, blue and pink) as well as common opal.

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