Type of opal
Types of opal:
According to color characteristics and optical effects, natural opal is divided into three categories: white opal (white opal), black opal (black opal) and fire opal (fire opal).
White Opal: As a gemstone with a long history, its basic colors are colorless, egg white, light gray, light yellow and light purple. After honing into a curved gemstone, the surface will show beautiful color. The bottom color is white, and the color is brighter.
Black Opal: Known by Australians in the 20th century. Its color is black, dark green, dark blue, dark gray and brown, and black is the best. The black opal surface shows a lot of color changes, and it is particularly bright and dazzling against the dark black background.
Fire Opal : It is a special variety in Opal. It is translucent to fully transparent and has a yellow and orange color. Since the diameter of the silica pellets constituting it is too small, it does not have a color change effect and belongs to a low-grade gemstone.
Distribution: Filling holes in caverns or ore in igneous rocks, forming stalagmites or stalactites, and replacing organic matter in fossil wood, animal hard shells and callus. Australia has been a major producer of opals since the 19th century. Others are the Czech Republic, the United States, Brazil, Mexico and South Africa.
Mother rock opal is more common in European and American markets, but is rarely known in China. It is produced in Australia and is very special due to the contact of silica-rich hydrothermal fluids with rocks in ancient times. Compared with ordinary opal, the parent rock opal is usually larger and the price is more intimate.
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