Silver Mining: The Lure of South Australia

Australia is mineral-rich country. It is one of the major exporters of silver to the world market. During British colonization, silver mining was the main attraction of South Australia, making it one of the most populated regions in the subcontinent.

Accidental discovery

Historically, silver was discovered by Cornish migrants Thomas and Hutchins in Glen Osmond in 1841. the story of the discovery was an accidental one. During one day in February, the two migrant's were travelling around Glen Osmond when their passing dray's wheel broke off a rock and exposed silver deposits underneath it. That very same year, the first mine named after Governor Gawler was established in the area. At the time, silver was a low value metal but the mine provided a big boost to a struggling colony on the verge of failure. The following years saw several more mines that greatly increased the economic standing of South Australia.

The silver production from South Australia has since then exceeded those of Mexico, Canada, and the USA. Today, Australia is already the leading producer of silver even after years of over a century of continuous production.

Processes

A large chunk of Australia's silver production is derived from silver-bearing lead mineral, galena. Other sources of silver come from gold and copper mining. At present, the method of silver mining in Australia are sophisticated and mechanized-digging deep underground by using earth tractors and drills that can penetrate miles beneath the ground. Ores are crushed and blown up in huge quantities, then loaded up to supersized loaders and trucks. On the ground, these ores are further processed by crushing and pulverizing them. Afterwards, galena is separated from tailings and waste rock particles using flotation method to produce pure concentrate.

Concentrates are then grounded, mixed with water and other chemicals, and stirred for a certain period in flotation cell banks. During this process, air is also blown to produce froths on the surface made up of fine silver bubbles. The waste products sink below. The bubbles are collected and skimmed to produce silver-lead sulphide pure concentrate of 0.8-1 kg of silver.

That's not the end of the process. The extracted silver concentrate is then partly melted to form lumps and eliminate sulphur dioxide. Them another smelting process follows in a blast furnace to create lead metals. Further refinement of crude lead will produce silver at last.

One of the most famous smelting plant and silver refinery is the Port Pirie. Silver mining is still considered the most lucrative business in Australia today. Years ago, silver mines and businesses made it to morning Australia news when the previous administration initiated large taxes for mining businesses all across the board. However, one thing remains in the coming years--that silver mining will continue to be a major economic force in the country, just like when it first started during the early years of Australia as a British colony.