In 75 AD, the Roman scholar Pliny compared opals to volcanoes and vibrant paintings, noting that their dancing “play” of rainbow colors could simulate shades of any gemstone.
Centuries of legends surround opal gemstones. During the Middle Ages, opal was thought to bring the wearer luck. However, that changed in the early 1800s when a story was published about an enchanted princess who wore an opal that changed colors with her moods. A few drops of holy water extinguished the stone’s magic fire, though, and the woman soon died.
Discoveries of opal deposits in Australia revived opal’s image after 1850. The country began producing 95 percent of the world’s opal gemstone supply and many of its finest opal specimens.
The world’s largest and most valuable opal, “Olympic Australis,” came from Coober Pedy, Australia in 1956, during the Olympic Games in Melbourne. Valued at $2.5 million in 2005, this gemstone measures 11 inches long and weighs 17,000 carats (7.6 pounds).
After scientists discovered the spherical silica structure of opal in the 1960s, they figured out how to create synthetic opal in 1974.
Since then, opal gemstones have gained more popularity through recent discoveries in Ethiopia. Material mined in the Shewa Province in 1994 wasn’t desirable because it was dark and tended to crack easily. Deposits in the Wollo Province, discovered in 2008, brought vivid play-of-color displays to the opal market.
Australia’s depleting supplies of classic opal have impacted the price of this uniquely kaleidoscopic gemstone. Because its flashing play-of-color can suit many changing moods and tastes, the opal stays in high demand.