Opal-mining is one of the world's most harrowing pursuits, but potentially one of the most rewarding as well. To find opals, a modern treasure hunter must dig random holes in areas of known deposits, and then lowering him- or herself down a 20 meter shaft. Besides the obvious problem of claustrophobia, and the danger of plummeting down a deep, narrow hole, opal mining holds some other horrors.
But for some adventure seekers, the danger and terror are still worth it.
Opal and the Australian Outback
Opal is often found in a raw, white form. A small, valuable percentage of opal, however, contains segments with refractive properties, allowing the surface of the stone to alter the angle of observed light and give off a red, blue, yellow or green hue.
Refraction adds tremendous eye appeal., and increases the value of this silica-based rock on the secondary market as jewelry, leading to a burgeoning opal mining industry.
The earth beneath Australia provides nearly 100% of the world's opal supply. Most of the Australian supply is found around the town of Coober Pedy, home to just roughly 1700 people, most of whom make their living and risk their lives conducting opal mining activities. Miners found the multimillion dollar Olympic Australis Opal, a three and a half kilogram opal with refractive properties, at Coober Pedy six decades ago in a shaft ten meters below the surface.
Over 200,000 of these mine shafts litter the area around the town of Coober Pedy, with additional shafts waiting to catch passerby across the Australian Outback. These evils of the Australian Outback, ideally, are supposed to be filled in or covered with sheet metal after mining operations cease — but many remain open to the air, endangering people and animals as they pass over the terrain.
Digging for treasure
Opal mining is conducted blindly — a miner may know the general location of an opal deposit (like the area around Coober Pedy), but there are no advanced techniques for narrowing down the location, since the opals are hidden within similarly structured but worthless rock.
A simple, hand-held black light will help point out opals with refractive properties, but these surfaces still need to be exposed by digging.
The majority of opal miners are self-employed, operating as a small business and renting or purchasing equipment as needed. Miners often prepare and sell the opal they find, eliminating a middle man in the jewelry trade and allowing the miners to maximize the amount of money of they can make.
The good news? You don't need much start-up money, thanks to the prevalence of previously dug shafts in the Outback. These existing shafts are left over from industrial mining operations, and opal hunters use them as a starting point, with these independent miners burrowing tunnels through the bottom of the existing shaft. Entering an old shaft is dangerous even with protective equipment, since these shafts can be flooded or have an insufficient oxygen supply.
Creating tunnels using homemade explosives
Once you're down an existing mining shaft, how do you create tunnels to get around? Using explosives (often homemade or mixed by the miners), plus equipment that vacuums dirt and debris up as the miners bore the tunnel. Opals can be found at any time in the process, but most opal is retrieved by sifting through the rock and debris created while making the tunnels.
Combining homemade explosives with 20 meter deep shafts sounds is a crazy idea, but we are talking about some pretty tough men and women here. As tunnels are extended, miners further expose themselves to dangers from sudden cave-ins.
Opal seekers often work on their own, leaving them without a safety or communication fail-safe if a life-threatening accident does occur. The financial reward and thrill-seeking nature of opal mining is enough to bring people back down the holes, with poor and new miners often using a series of ladders or winches precariously attached to the front of their trucks to lower them down to the hunting grounds.
Searching for opal is not just carried out for profit, but it is also a recreational activity in some parts of the Outback. Vacationers often "fossick" through small holes or leftover mounds of extracted dirt already sifted through by experienced miners.
But what happens when the Outback runs out of opals, or is closed off to mining in the future? In that case, civilization could turn to Mars to feed all its opal gemstone needs.
Top image is a sunset over an opal mining shaft at Coober Pedy via David Webster/Flickr. Additional images from JJ Harrison/CC and Simon Brown/Flickr. Check out Stuart Bird's blog for a rambling, hilarious, and very detailed personal account of life as an opal miner.