Opal mining - you never know your luck

It’s as dinkum Aussie as a bucket of prawns and an ice cold beer, and a mining activity that is the antithesis to the practices of modern mineral extraction.   BY ALAN TITCHALL.

Opal is one of the few minerals still extracted economically by a lone miner noodling about the surface with a shovel, sieve and a keen eye. Even using modern equipment, opal mining in Australia remains small scale.

The challenge to locate, scientifically fingerprint, and estimate the value of any opal resource (effectively silica in clay deposits), has thwarted large scale exploration and kept the opal mining industry driven by individuals, mum and dads, and small companies armed with a local prospecting permit and a strong gambling itch.

 Unlike many other gemstones, opal does not occur in large lengthy veins or in diamond-like concentrations. Small clusters of gem-quality material may be scattered over a vast area many kilometers in each direction and finding it relies on a lot of good ole prospector’s luck. The more valuable precious opal also represents a remarkably small percentage of the total opal mined and fine gem quality opal is actually more rare than rubies and emeralds.

Australia produces and exports over 95 percent of the world's precious opal, with the industry contributing between A$200 million and A$400 million to the national economy over the past decade. Most of this supply is mined at only three small areas - Lightning Ridge 770 kilometres north of Sydney (famous for its black opal); Mintabie at Coober Pedy in South Australia; and Andamooka just southwest of Coober Pedy.

The lack of new fields, tighter mining regulations, native title restrictions, environmental consent obligations and cost increases, have all taken their toll on the industry, which has been declining over the past decade. 

Up until the late1980s, the small-scale nature of the industry was reinforced by state government legislation. That was until South Australia Queensland opened up exploration opportunities for large companies, and New South Wales allowed for exploration licenses with full size flow-on mining title (restrictions still apply to the established opal fields of the Lightning Ridge and White Cliffs - now reserves).

However, cost effective large-scale mining is an opportunity still waiting. Opal exploration is mostly by drilling – a costly exercise in the remote Australian Outback, and the large mines operating under mining leases in recent years are open-cut operations using heavy equipment to work mostly areas of old workings.

As most old opal diggings have now been largely worked out, or reworked by open-cut methods, well-resourced and systematic exploration to find new prospects over known opal bearing country is essential for the future of the industry.