|Billed as the “finest opal ever,” the Virgin Rainbow made its world debut at the South Australian Museum in Adelaide in September as the centerpiece of a larger exhibition to commemorate the centenary of opal mining in Australia.|
|Veteran miner John Dunstan is credited with discovering the Virgin Rainbow in the desert soil of Coober Pedy in South Australia in 2003.|
Dustan has mined opals for 50 years, but the internal fire of the Virgin Rainbow is unlike anything he’s ever seen.
Gibber plain near Coober Pedy
|Dustan explained that the Virgin Rainbow is a Belemnite pipe, which is essentially an opal that formed in the skeleton of an extinct ancestor of the common cuttlefish. As Dustan cleaned it off, he realized he made a once-in-a-lifetime discovery.|
“I knew it was one of the best ever,” he said. “You’ll never see another piece like that one, it’s so special.
|Coober Pedy is often called “The Opal Capital of the World.” The discovery of gem opals sparked a rush of mining activity that has generated top-quality gems for the past 100 years.|
Australia produces more than 90% of the world’s precious opals.
|Between 100 million and 97 million years ago, Australia’s vast inland sea began retreating. As the sea regressed, a rare episode of acidic weather was taking place, exposing pyrite minerals and releasing sulphuric acid.|
As the surface of the basin dried further and cracked, silica-rich gel became trapped in the veins of the rock. Over eons, the silica solidified to form opals
|Coober Pedy, an Aboriginal name meaning "White man in a hole", adequately describes the mines and miners' dwellings - burrows dug into the scarp, in order to escape soaring temperatures of the day and the freezing winds at night.|