The “Butte Nugget,” believed to be the biggest gold nugget unearthed in modern times, was displayed and put up for auction at the San Francisco Fall Antiques Show on Thursday.

6-lbs Gold Nugget Up For Auction

The gold nugget is impressive in size, measuring about 7-by-4 inches and weighing an astounding 6.07 pounds. It is being sold by coin dealer Don Kagin, as the owner of the Butte Nugget wishes to remain unnamed. The owner has also refused to disclose the exact location of his discovery to the press, for fear of causing another gold rush of sorts. What is known is that the nugget was discovered in Butte County (hence the Butte Nugget moniker) – part of the historic California Gold Country.

Kagin assured the public that his team has vetted the authenticity of this gold nugget, though even David McCarthy, the numismatist assigned to authenticate the nugget doesn’t know exactly where the nugget was found.

“I can’t say the actual location of where this nugget was found, though I had to be blindfolded for the ride out to the location, so I couldn’t say exactly even if I wanted to,” McCarthy told the San Francisco Chronicle.

Butte Nugget Expected To Sell For $350,000

In 2011, Kagin was tricked into selling an 8.2-pound nugget of gold he was led to believe came from Gold Rush Country, and was forced to buy back the gold and sell it at a loss when it was discovered that the gold did not come from California, but from Australia. This time, Kagin says he made absolutely sure the gold nugget was not only real, but also from Butte County as the owner claimed.

“This one’s for real. Obviously we don’t want to get hoodwinked again, so we have checked pretty thoroughly into it,” Kagin said.

Melted down, the nugget is estimated to be worth around $85,000, but it’s unique nugget shape and its Gold Rush Country origins add enormous historical value. The Butte Nugget is expected to sell for at least $350,000.

The Butte Nugget will be on display through Sunday, Oct. 26.