Boulder opal is becoming more and more popular. Australia’s central Queensland is home to more than a dozen of sources of this stone. Come with GIA field gemmologists to find out more about this unique gem.
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Lightning Ridge is the world capital of fine black opals, the most desired of all opals. In June 2015 a group of GIA field gemmologists visited this legendary town in New South Wales, Australia. Come with us to explore this important source of fine opals.
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Documents a trip to the renowned opal fields of Lightning Ridge, Koroit, Yowah and Quilpie.
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All jewellery professionals are familiar with the city of Shenzhen, a global jewellery manufacturing centre and a leader of China’s fast-growing gem and jewellery industry. Join the GIA team as we tour the city and discover more about its leading jewellery brands.
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The properties of petrified woods originating from various localities in Thailand and Myanmar are examined.
Read MoreOpal occurs as nodules in volcanic rocks at a new gem opal locality in the Menz Gishe district of Shewa Province, Ethiopia.
Read MoreAfter almost 75 years of inactivity, the deposits of boulder opal in Queensland, Australia, began to attract new interest in the 1960s and 1970s.
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Matrix opal from Andamooka, in South Australia, is a precious opal-included porous rock that is commonly colour enhanced (carbon impregnated) to imitate the highly prized black opal from Lightning Ridge in northern New South Wales, Australia.
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Recent mining at Opal Butte in northeastern Oregon has produced a wide variety of large flawless opals.
Read MoreGemmological and chemical analysis of bright green gem-quality opal from Tanzania.
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