Opal

“Of all precious stones, it is Opal that presents the greatest difficulties of description, it displaying at once the piercing fire of Ruby, the purple brilliancy of Amethyst, and the sea-green of Emerald, the whole blended together and refulgent with a brightness that is quite incredible.”

Pliny the Elder (23-79 AD), Historia Naturalis

Etymology

The name ‘Opal’ derives from the Latin ‘opalus,' which in turn stems from the Greek ‘opallios,' meaning ‘seeing a change.' Another possible Greek etymology is ‘opthalmios’ (gem of the eye), but the original source of the name is likely the Sanskrit ‘upala’ (precious stone), which lends credence to the belief that India was once a source of Opal for Ancient Rome.

Chemical composition of Opal

pebble-opal.jpg

Boulder Opal

Opal’s structure is unique, and consists of minuscule spheres of silicon dioxide aligned in a pyramid-shaped grid. It’s the refraction of light through the spaces between these spheres that produces Opal’s characteristic and unique ‘play of color’ - the flashes of color that change with the angle of observation. Interestingly, Opal without ‘play of color’ such as Mexican Fire Opal has its silicon dioxide spheres more randomly arranged.

Opal extraction

Opal is extracted from sedimentary rock, where it fills cavities or veins. Extraction from deposits, along with the selection and cleaning of raw Opal, is done by hand.

Today, 95% of Opal with play of color is sourced from a handful of Australian mining areas, including Andamooka (discovered in 1930), Coober Pedy (1915), Lightning Ridge (1902), Mintabie (1931), White Cliffs (1890) and the Queensland Boulder Opal fields (a vast area discovered in 1869 surrounding the town of Quilpie). The marvelous, bright colored Welo Opal is extracted in Ethiopia. Sources of Opal without play of color are located in Brazil, Peru, Mexico and Tanzania.

The history of Opal

A gemstone with as many varieties as Opal is surrounded by numerous legends and traditions. For a long time, it was used as a talisman, believed to bring fortune and success to the wearer. The Ancient Greeks believed that Opal allowed one to see the future, while the Ancient Romans saw it as a symbol of hope and purity. The Arabs believed that Opals had fallen from the sky with a lightning bolt, and thus could protect against lightning bolts, in addition to conveying invisibility.

For tribes from the Andamooka region in South Australia, the Opal was known as the ‘fire of the desert’ and was linked to creation myths. Their ancestral creator came down to earth on a great rainbow, which turned the rocks it touched into resplendent Opals, colored with the hues of a rainbow. In reality, we need to look to a huge inland sea and a resulting geological feature called the ‘Great Australian Basin’ to understand the origins of this gemstone. The majority of Australia’s Opal fields are located in the basin and were formed from the weathering of sandstone deposited over older host rock.

black-mystic-opal.jpg

The mysterious Black Opal

Properties of Opal

Opal is well-loved for its unique play of color and flashes of light that change depending on the angle of observation. In addition to its multi-colored brilliance, Opal is also sought after for its stability - an important criterion when grading a gemstone that contains six percent water. A typical phenomenon is the so-called ‘opalescence,’ a gentle shining light that slips across the surface of the gemstone. The cause is interference; light diffuses through the subtle layers of the stone, creating this marvelous visual effect.

Varieties of Opal

Opals with color play are distinguished based on the host rock (also called ‘pots’ or ‘matrix’) on which Opal forms and their resulting transparency and body color (the base color on which Opal’s ‘play of color’ is visible).

mexican-fire-opal.jpg

Mexican Fire Opals

Black Opal has a black body color and may be opaque with some translucency, particularly when held to a strong light source. Gray Opal is a term seldom used, with its specimens typically being grouped in the ‘black,' ‘dark’ or ‘semi-black’ categories, but it is translucent to opaque with a gray body color.

White Opal, also called ‘Clear Opal’ is a popular and contemporary stone. It may be translucent or opaque, with a white body. Welo Opal displays an electric neon color and various patterns on a predominantly white body, although some examples are yellow or amber. Jelly Opal may be transparent or translucent, and due to the absence of host rock is either colorless or, viewed more optimistically, is called ‘Crystal Opal,' ‘White Crystal Opal,' ‘Dark Crystal Opal’ or ‘Black Crystal Opal.'

Opals with the matrix (host rock) included in the cut are called Boulder Opals; every Opal with host rock visible on the surface is called ‘Matrix Opal.'

Not all opals show a play of color, however. Fire Opal is a transparent to translucent crystal Opal with virtually no ‘play of color,' displaying oranges, reds, yellows and, since a recently discovered Brazilian deposit, also blues. Buriti Fire Opal is sourced in Brazil, and enchants with its reds and oranges, reminiscent of Mexican Fire Opal. Peruvian Opal is a rare variety that exhibits exquisite translucent blues, pinks and greens, also without play of color. Another variety without play of color is the translucent Yellow-Green Opal from Tanzania.

 

One of the rarest opals is the Australian Black Opal, but the difference in quality can change the pricing dramatically (see our Australian Black Opal Chart or Videos). The rarest opal we own is the "Flower Blossoming," Peruvian Ice Blue edged with delicate mulberry which we own in a matched pair. We have never been able to locate another for a pendant since they are almost never on the market and to have a matched pair is ridiculously good fortune, they are coveted.

5/5  - in relation to Welo is perfect color and perfect brightness.

 

17 products
SOLD 1.10 ct. Ethiopian Welo Opal, Top 5/5 Brightness and Color
SOLD 1.10 ct. Ethiopian Welo Opal, Top 5/5 Brightness and Color
Sale
Regular price $174.00 $42.00 Sale
Ice Blue Peruvian Opal, Round Diamond Cut 2.80ct Master Cut in Germany
SOLD 2.80 Carat Faceted, Peruvian, Diamond Cut, Ice Blue Opal, Master Cut in Germany
Regular price $189.80
Australian Opal, Untreated, Fabulous Color, Rare Orange, Top Colors
7.20 ct. Australian Opal, Untreated, Fabulous Color, Rare Orange, Top Colors
Sale
Sold out
Regular price $3,400.00 $1,241.00 Sale Sold out
PURPLE/BLUE/GREEN Colored Vein Solid Koroit Australian Boulder Opal, Rare
Koroit Australian Boulder Opal, Rare PURPLE/BLUE/GREEN Colored Vein
Sold out
Regular price $98.00 Sold out
4.80 Ethiopian Welo Opal, Brush Painting Pattern 5/5 Color and Brightness VIDEO
Sale
Regular price $345.67 $197.50 Sale
5.30 Ethiopian Welo Opal, 5/5 Brightness and Color Rolling Pinfire 3-D
Sale
Regular price $510.00 $350.00 Sale
4.80 ct. Ethiopian Welo Opal 5/5 Oval Cabochon, Honeycomb Top Fire
4.80 ct. Ethiopian Welo Opal 5/5 Oval Cabochon, Honeycomb Top Fire
Sale
Regular price $409.00 $280.00 Sale
4.50 ct. Ethiopian Welo Opal, Pear Cabochon, Top Fire
Below wholesale! 4.50 ct. Ethiopian Welo Opal, Pear Cabochon, Top Chaf Fire
Sale
Regular price $280.00 $116.00 Sale
14.15 ct. Ethiopian Welo Opal, Full Fire, All Colors, 5/5 Rating Top Quality SEE VIDEO
14.15 ct. Ethiopian Welo Opal, Full Fire, All Colors, 5/5 Rating Top Quality SEE VIDEO
Sale
Regular price $5,970.00 $4,900.00 Sale
Ethiopian Welo Opal 14 carat, Pear Shaped Cabochon, 3-D Rainbow Patchwork
Ethiopian Welo Opal 14 carat, Pear Shaped Cabochon, 3-D Rainbow Patchwork
Sale
Regular price $6,015.00 $3,800.00 Sale
15.65 ct. Ethiopian Welo Opal, Round Cab, High Dome, Flagstone Pattern
15.65 ct. Crystal Opal, Round Cab, High Dome, Flagstone Pattern
Sale
Regular price $5,957.00 $4,990.00 Sale
Large Vivid Fancy Red Mexican Fire Opal, Trillion Cut 6.44 ct
Large Vivid Fancy Red Mexican Fire Opal, Trillion Cut 6.43 ct
Sale
Regular price $3,934.00 $2,470.00 Sale
Highly Transparent Blood Red-Red, Fire Opal
1.40 Carat Fire Opal, Highly Transparent Blood Red-Red
Sale
Regular price $398.00 $267.00 Sale
9.50 Carat Fantastic, Dominant Red, Mexican Matrix Opal, Multicolor, Cantera, Lost World Look
9.50 Carat Fantastic, Dominant Red, Mexican Matrix Opal, Multicolor, Cantera, Lost World Look
Regular price $69.00
Blue Mexican Matrix Opal, Landscape, Cantera 9.0 Carats
9.0 Carat Blue Mexican Matrix Opal, Landscape, Cantera
Regular price $56.00
8.65ct Rare Colored Blue-Violet Brazilian Opal, Pear Shape
8.65 Carat Rare Colored Blue-Violet Brazilian Opal, Pear Shape
Regular price $310.00