Where is Opal Mined?
Where is Opal Mined?
Opal is undoubtedly the most diverse, unique and beautiful birthstone associated with the month of October. Unlike most gemstones, it does not have a defined crystalline structure as it takes on many shapes and colors. This gemstone is known for its unique color combination, which acts as its bar code that varies from stone to stone. But, no two stones will ever be the same even if they come from the same place in the same mine.
This is Nature’s way of bringing in a gemstone curated differently each time it is excavated and processed. Due to its beautiful color combinations, the gemstone has been restricted to the fashion and jewelry industry.
This is why knowing where Opal is mined from is important because the demand is steadily increasing beyond the available supply in the market.
The Mining Sources of Opal
Since Opal is known for its color combination, it doesn’t come in one specific color like other gemstones such as turquoise or emerald. But what is important to know is the gemstone occurs because that determines the geological regions where its mines are located.
Since Opal is a hydrated amorphous form of silica, the precious and gem-quality version of Opal is formed of silica spheres in a diameter. These silica spheres create diffraction of light, which causes you, as the viewer, to see the different combinations of colors due to how the light has split apart. So, in short, the size of the silica spheres and the way they are packed together determines the quality of the Opal. Opal will normally occur in fissures of limonite, sandstone, marl, basalt, and rhyolite, which means it is limited to only specific countries with these types of rocks.
Currently, Opal is mined in Australia, Ethiopia and some counties in the United States of America
Australia
The country is considered to supply nearly 80% of the world’s opals. That is reason enough that it has claimed the colorful gemstone as its national and official gemstone depicting its heritage and culture. The major mines for Opal in the world are found in Australia in three locations. The three states are Queensland, South Australia, the ‘Great Artesian Basin’, and New South Wales but each state specializes in a different kind of Opal. For instance, Queensland mines are known for boulder opals. In contrast, black opals are exclusively found in New South Wales and milky opals in South Australia.
Hence, it is no surprise that Australian opals are the most expensive in the world. With the most expensive uncut Opal valuing at $675,000 known as the ‘Fire of Australia’. The world’s largest and most valuable opal ‘Olympic Australis’ was founded in August 1956 at the Eight Mile opal field in South Australia. Another mine located in Andamooka in South Australia is also a major producer of matrix opal, Black Opal, and crystal opal.
That means that Australia is the top producer of Opal, with its mines being a storehouse of different variations and color combinations of opals.
Ethiopia
One would not think of Africa when it comes to mining sources of Opal, and yet the country Ethiopia is known to have its mines operated for Opal since 4000 BC. This was when the gemstone was used to make tools. But, the first published report of a gem-quality opal from Ethiopia had appeared in the public eye towards the end of the 20th century. Can you guess which year exactly? None other than 1994.
The gem-quality Opal was discovered in Menz Gishe District in North Shewa Province of the country. However, all was not well because the Opal found in this area was dark brown and had a tendency to crack. This means its silica spheres were not the right size, and hence, the light was not able to split itself, so there was no color display. Hence, it became unpopular, but in 2008 another opal mine was found roughly 180 kilometres north of the Shewa Province in the Wollo Province. The opals found in the Wollo Province were extremely different to the range of opals in size, color and quality that had been found commonly in other provinces. The opals here are of a higher and much better quality, closely resembling to those found in Australia or Brazil with vivid color combinations.
If you notice, the Wollo opals are in stark contrast to the brown opals found in the Shewa Province. That’s like comparing a real precious gemstone to a rock. It is no wonder that these opals known as ‘Wello’ are the dominant Ethiopian opals and have brought the country fame in the gem market.
Nevada in the United States of America
The region within the American land is known for producing gem-quality black, fire, crystal, and lemon opals. With the black fire opal being Nevada’s official gemstone. The Opal is found in deposits of bentonite. However, some uncut opals do have high water content, so they are more vulnerable to cracking. The main mines are located in Virgin Valley within Nevada, with the biggest mines being Rainbow Ridge, Bonanza, Royal Peacock, and Opal Queen.
Our Final Thoughts
Opal is primarily associated with Australia because it is the country’s national gemstone, and the Australian opals are considered the most genuine and the hallmark. They are used as a standard to compare the quality, size, and color of opals mined in other countries. The proof is in the story of Ethiopian opals upgraded based on their resemblance to Australian opals.
