Henry Dole, a miner from the nearby township of Kambalda, has been credited with the discovery when he drilled holes into the wall of the mine and detonated explosives that uncovered the “unprecedented” quantity of gold.
"Everything was covered in dust, and as I watered the dirt down there was just gold everywhere, as far as you could see," Dole told the ABC.
"I've been an airleg miner for 16 years. Never in my life have I ever seen anything like this.”
The largest specimen of quartz rock weighed 90kg and was covered in an estimated 2,300 ounces of gold, believed to be valued at $3.8 million while another 60kg specimen contained 1,600 ounces that could fetch $2.6 million.
The mine, owned by Canadian company RNC Minerals, had been mined for nickel prior to the discovery made 500m below the surface.
RNC president Mark Selby said the gold-encrusted rocks will be auctioned and the company anticipated collectors would be most interested in purchasing the pieces for their collectables value rather than for their estimated value in gold.
"Given the rarity of the rock, and the physical beauty and presentation of the gold that's there, it's a very spectacular stone in multiple ways, so we'll see whether 20, 30 or even 50 per cent premiums apply here," he told the ABC.
"We're really looking forward to auctioning the key stones off over the coming weeks. There's a pretty select group of collectors who this would appeal to.
"When you look at nuggets, which are a solid piece of gold, the biggest are around 2,000 ounces, so this is right up there in terms of the largest specimens we've ever seen."
It was a shock discovery for the township of Kambalda, which has been going through hardship with four major mine closures in three years resulting in hundreds of job losses.
"It's no secret we were looking down the barrel for a while, but with this, it's picked everyone's morale up," Selby said.
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