On the Road to Coober Pedy, Part II

The serendipity of the geologic and climatic conditions required for opal formation-which occurs at the rate of about one-quarter-inch per five million years-is extremely rare. This is the breakfast topic in our miner-mate Robin’s dugout home at Coober Pedy in the South Australia desert, where, it is claimed, almost 90% of the world’s precious opal is found. According to Bernie, the opal-forming processes beneath Coober Pedy began 128 million years ago, when Australia lay near an iceless South Pole, in two pieces separated by an ocean. The description conjures visions of a lunar landscape, not unlike the region north of town called “The Breakaways”-source of the region’s best opal.

The region is described geologically as an escarpment over a fault in the crust of the earth. Geologists say the escarpment became a feature when developing ice sheets caused the earth’s shallow seas to dry up. The silica concentrations of the seas drained into rock cavities, and the opalizing process began. Each opal fragment is unique in how it refracts and reflects light. This is determined by how tightly and uniformly atoms of silica gel have bonded, along with how much of the mineral cristobalite the opal contains.

Don’t back up. Opal has been mined here since 1915. In the desolate outback, the success of a new mining field depends upon whether underground water can be found within a reasonable distance. Precious opal diggings at Mintabie, on the road north to Alice Springs, now stand abandoned for lack of water. Here in Coober Pedy, the precious liquid comes from 200-foot-deep wells via a 15-mile-long, five-inch-bore plastic pipe maintained by the state government. The water costs about 15 cents (US) per seven gallons. It’s desalinated before being reticulated and must serve about 3,500 people-the majority of them hard-working men in the desert.

The legacy of 85 years of mining in Coober Pedy is a 60-mile-long by five-mile-wide labyrinth beneath the desert. It’s no place to go unescorted. According to Robin, “about a week” is as long as anyone has survived after “wanderin’ off.”

“You can’t hear any yelling once someone goes around a few corners,” Robin warns visitors. “The tunnels all look the same, and you can easily get lost.” In August of this year, a 73-year-old miner was unable to return to the surface when his power winch malfunctioned. He fell 50 feet from a ladder, broke a leg, and lay for four days before a friend found him and took him to the town hospital. “He’s going to be okay,” rescuer Boro Rapaic reports. “Opal mining makes you tough.”

Apart from miners’ mishaps and serious claim jumpers, the people most in danger of falling down holes in Coober Pedy today are tourists walking backward as they take photographs.

How’s business? Complaints by opal miners about opal buyers are nearly universal. “The price they offer here for opal does not make it worthwhile going after half the time,” declares Miners Association president Dave Westneat. “It hardly pays for explosives,” says miner and electrician Big Carl, who’s fixing Robin’s washing machine.

Westneat claims the average member makes less than US$50 for each cubic yard of opal-bearing porcelainite rock processed. “It’s hard holding out for more money when you’re going rough, mate,” he says. “They start waving a bit of cash around, and before you know it, your best opal has gone.” All miners, however, hold on to their best opal, hoping for top dollars from somewhere.

To contact the Coober Pedy Miners Guild, call Robin Hutchins in Potch Gully at (61-88) 672-3068.

Next month: Ka-boom! JCK goes mining in Coober Pedy.