Two quartz rocks containing gold have been removed from 500 metres underground, the biggest of which weighs 90 kilograms and contains an estimated 2,300 ounces of gold, worth 2.7 million U.S. dollars at today's price.
The other rock weighs 60 kilograms and contains around 1,600 ounces of gold worth 2 million U.S. dollars.
Early estimates have put the take of gold from the deposit overall at around 9,000 ounces.
Located about 600 kilometres west of state capital Perth, the Beta Hunt mine is owned by Canadian company Royal Nickel Corporation (RNC).
Up until now its main business is on a nickel mine, with gold of secondary interest.
"This is one of those once-in-a-lifetime moments where people find 2,300 ounce and 1,600 ounce chunks of gold," RNC chief executive Mark Selby said.
"It's generally an exciting moment, and given it's been a tough slug for us at the mine, to make this kind of discovery just reinforces that we always knew this mine had potential."
The miner who made the discovery, Henry Dole, said that in his 16 years working in the industry, he had never seen anything like it.
"As I was drilling it, you could see the gold shavings coming out of all the holes and I thought -- there's something here."
RNC said that while most gold discovered in the area is melted down into bars, the rarity of the larger stones means that they may be more valuable to a collector in their present condition.
"We're really looking forward to auctioning the key stones off over the coming weeks," Selby said.
Beta Hunt mine is currently up for sale by RNC who say they are unable to front the capital for proper exploration of the area, making the million dollar question -- "how much more remains to be found?"
Dole, who has seen a number of mines in the area close in recent years said that he believes there's something bigger and better just beneath the surface.
"I reckon we're just on the fringe of it, and if we get deeper I reckon we'll find more."