THE IRIDESCENCE WITHIN AN OPAL IS A PERFECT MATCH FOR A VIBRANT MAGICAL LIFE
Iridescent Opals are dazzling and enigmatic, with different hues dancing within one stone like a Kaleidoscope! The word comes from the Latin opalus, meaning “precious jewel,” and from the Greek word opallios, meaning “to see a change in color.” Opals can display unique, one-of-a-kind blends of colors, from serene flashes of deep blues and sea greens to bright and fiery reds and yellows, all in a single gem. As you turn and move the gem, the light shifts displaying infinite combinations of bright colors caused by precious Opals' unique iridescent or play-of-color properties.
Opals can be precious (shows play-of-color or iridescence), common (has no play-of-color/iridescence, but displays opalescence a hazy milky sheen) or fire (transparent vivid red-orange, rarely has play-of-color or iridescence). The Starling opal is a precious light opal, so this post is mostly about precious opals. We do love the other two types of opals though!
HISTORY OF OPALS
Geologists believe that opals were first mined in Ethiopia around 4000 BC. In 1939, archeologist Louis Leakey discovered opal artifacts in the “Nakuru” cave in Kenya, which were dated to be over 6000 years old. This discovery has led researchers to believe that these opals were likely traded by the Ethiopians with the Kenyans, placing the earliest known source of Opals in Ethiopia.
In the 18th century, Hungary was the major opal producer with mines in the Dubník and the Tokaj Mountains, near the village of Telkibánya. Here, precious opals were mined including a special transparent yellow-orange common opal called honey opal. However, by the turn of the century, mining in Hungary slowed, and today new mining of Hungarian Opals is unheard of.
Today, Australia is the hotspot for opal mining, especially since the 19th century when high-grade opals were discovered in Southern Australia. Today Australia accounts for over 80% of the world supply. The world's largest and most valuable gem opal "Olympic Australis" was found in August 1956 at the "Eight Mile" opal field in Coober Pedy in Southern Australia. It weighs 17,000 carats and is 11ins long. Opal is the national gemstone of Australia. The Lightning Ridge region in Australia is known worldwide for its deposits of rare and stunning Black Opal.
However, since 1994, Ethiopia is also once again the rising star in opal production with the discovery of precious opal in the Menz Gishe District, North Shewa Province, and then in Wollo Province. The Wollo Province opal was different from the previous Ethiopian opal finds in that it more closely resembled the sedimentary opals of Australia and Brazil, with a light background and often vivid play-of-color. Wollo Province opal, more commonly referred to as "Welo" or "Wello" opal, has become the dominant Ethiopian opal in the gem trade.
CHEMICAL AND MYSTICAL PROPERTIES
Opal is a hydrated amorphous form of silica (also used to make glass) and can be up to 20% water by weight. The play-of-color in precious opal is caused by the internal structure: layers of spheres of silica. When light enters the opal it diffracts, bouncing between the spheres and in the spheres and splitting like a prism. When the light exits the stone we see the beautiful colors. Opal deposits are found at low temperatures and in the fissures of almost any kind of rock, including sandstone, and basalt. The colors opals show depend on the conditions when it was formed. Precious opals are categorized by their transparency and bodycolor or background color. The 5 main types are White or Light (like the Starling one) Opal, Black opal, Fire Opal, Boulder Opal and, Water or Crystal Opal.
Opals were considered rare and extremely valuable in antiquity, especially in Europe where they were the pride and joy of royalty. The Romans thought opals to be the most valuable and powerful gem of all due to its myriad rainbow hues, while the Bedouins believed that opals were a symbol of lightning, falling from the sky during thunderstorms. In the Middle Ages, opals were thought to possess all the virtues of each gemstone whose color was represented in the color spectrum of the opal and thus provide great luck. Throughout time and cultures, opals have been a lucky and powerful mystical gem, with so much wonder and color radiating from them it’s no wonder. They do look magical!