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Black Opal Peacock

Black Opal Peacock

Opals are described according to their transparency and body color. Opals with a vivid play-of-color and a black or other dark body color are called black opals. Top-quality black opals are highly prized and were discovered in the legendary Lightning Ridge opal field in Australia in 1903. Opals are typically cut as cabochons or polished free form to best show the play-of-color. The Opal Peacock Brooch was designed by Harry Winston, Inc., and features a 32-carat black opal from Lightning Ridge, Australia. The opal is accented with sapphires, rubies, emeralds, and diamonds set in yellow gold. The Opal Peacock was donated to the National Gem Collection by Harry Winston in 1977.

Black Opal Ring

Black Opal Ring

Opals are described according to their transparency and body color. Opals with a vivid play-of-color and a black or other dark body color are called black opals. Top-quality black opals are highly prized and were discovered in the legendary Lightning Ridge opal field in Australia in 1903. Opals are typically cut as cabochons or polished free form to best show the play-of-color. This 26.9 carat black opal from Lightning Ridge, Australia exhibits a brilliant play-of-color and is of superb quality.

Dark Jubilee Opal

Dark Jubilee Opal

Opals are described according to their transparency and body color. Opals with a vivid play-of-color and a black or other dark body color are called black opals. Top-quality black opals are highly prized and were discovered in the legendary Lightning Ridge opal field in Australia in 1903. Opals are typically cut as cabochons or polished free-form to best show the play-of-color. The Dark Jubilee Opal pictured here is a 318.4-carat free-form polished black opal from a mine in Coober Pedy, Australia, another famous region known for black opals. Coober Pedy means "a man in a hole" in a regional aboriginal language, and many miners do live in the underground excavations there. The Dark Jubilee Opal was a gift of the Zale Corporation in 1980.

Mexican Fire Opal

Mexican Fire Opal

Opal is a noncrystalline hydrated form of silica, forming when silica slowly settles out of a dilute water solution. Fire opals are transparent to semi-transparent, resembling gelatin, with red, orange, or yellow body color, with or without play-of-color. Fire opal gets its name from its reddish orange body color, which is caused by inclusions of iron oxides. They are also sometimes called Mexican opals because most of the best fire opals are found in Mexico. Because of their transparency, fire opals are commonly faceted, as seen here.

Mexican Fire Opals

Mexican Fire Opals

Opal is a noncrystalline hydrated form of silica, forming when silica slowly settles out of a dilute water solution. Fire opals are transparent to semi-transparent, resembling gelatin, with red, orange, or yellow body color, with or without play-of-color. The body color is caused by inclusions of iron oxides. They are also sometimes called Mexican opals because most of the best fire opals are found in Mexico.

Opal

Opal

Opals from Mezezo, Ethiopia have been well-known for more than 10 years for their play-of-color chocolate opals. Other deposits discovered more recently from Welo yield precious white, fire, crystal and sometimes black opals. The opal you see here is an 8.86 carat chocolate opal from Mezezo. Gem opal consists of tiny silica spheres tightly packed together; the voids or spaces between the spheres contain air or water. The play-of-color in opal is due to the orderly arrangement of these spheres acting like a diffraction grating, breaking visible white light in to separate colors. Opals are typically cut en cabochon or polished free-form to best show the play-of-colors.

Opal

Opal

Opals from Mezezo, Ethiopia have been well-known for more than 10 years for their play-of-color chocolate opals. Other deposits discovered more recently from Welo yield precious white, fire, crystal and sometimes black opals. The opal you see here is a crystal opal (33.15ct) from Welo. Gem opal consists of tiny silica spheres tightly packed together; the voids or spaces between the spheres contain air or water. The play-of-color in opal is due to the orderly arrangement of these spheres acting like a diffraction grating, breaking visible white light in to separate colors. Opals are typically cut en cabochon or polished free-form to best show the play-of-colors. This beautiful Ethiopian opal is a wonderful addition and upgrade to the National Gem Collection and the first from Welo.

Opal

Opal

Opals from Mezezo, Ethiopia have been well-known for more than 10 years for their play-of-color chocolate opals. Other deposits discovered more recently from Welo yield precious white, fire, crystal and sometimes black opals. The opal you see here is an uncut crystal opal (643.9ct) from Welo. Gem opal consists of tiny silica spheres tightly packed together; the voids or spaces between the spheres contain air or water. The play-of-color in opal is due to the orderly arrangement of these spheres acting like a diffraction grating, breaking visible white light in to separate colors. Opals are typically cut en cabochon or polished free-form to best show the play-of-colors. This beautiful rough Ethiopian opal is a wonderful addition and upgrade to the National Gem Collection and the first from Welo.

Opal (variety: Black)

Opal (variety: Black)

The Roebling Opal is an extraordinary piece of opal rough from Virgin Valley, Nevada. The opal was deposited from silica-rich water in voids that remained after buried tree limbs had rotted away, in some cases resulting in opal casts of the original tree parts. Although extremely beautiful, opal from this locality is not commonly used in jewelry because it tends to craize, or crack.

Opal (variety: Fire)

Opal (variety: Fire)

Fire opals are transparent to semi-transparent, resembling gelatin, with a red, orange, or yellow body color, with or without play-of-color. The body color is caused by inclusions of iron oxides. Gem opal consists of tiny silica spheres tightly packed together; the voids or spaces between the spheres contain air or water. The play-of-color in opal is due to the orderly arrangement of these spheres acting like a diffraction grating, breaking visible white light in to separate colors. Fire opals are commonly referred to as Mexican opals because most of the finest fire opals are found in Mexico. Opals are typically cut en cabochon or polished free-form to best show the play-of-colors. However, due to their transparency, many fire opals are faceted. This fire opal cabochon is semi-transparent with an orange body color and displays beautiful green, yellow, orange and red play-of-color. With magnification, looking inside the opal you can see interesting inclusions: "stalagmite and stalactite" formations that are probably goethite rods, along with what appear to be hematite crystal inclusions. This Mexican fire opal has all the characteristics of a unique and beautiful gemstone and is a wonderful addition to the National Gem Collection.

Opal (variety: Fire)

Opal (variety: Fire)

The "Hologem" pendant features a round faceted fire opal gem mounted in 18k yellow gold and accented with diamonds. The concave high-polish metal captures and reflects the opal’s color giving the appearance of a larger gemstone. The complex optical design gives the pendant a 3-D or holographic appearance, hence the name, "Hologem". The fire opal, from Mexico, is an intense orange-red color. The pendant was designed by jeweler, Gregory Crawford.

Tiffany Black Opal Necklace

Tiffany Black Opal Necklace

Opals are described according to their transparency and body color. Opals with a vivid play-of-color and a black or other dark body color are called black opals. Top-quality black opals are highly prized and were discovered in the legendary Lightning Ridge opal field in Australia in 1903. Opals are typically cut as cabochons or polished free form to best show the play-of-color. This opal and gold necklace designed by Louis Comfort Tiffany about 1915-1925 is accented with brilliant green demantoid garnets from Russia. The black opals are from Lightning Ridge, Australia.


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