NEVADA CITY, CA (AP).- A 6.2-pound hunk of gold was auctioned for nearly half a million dollars in March after a man claimed he found it on his Sierra Nevada property, but it turns out it was actually dug up decades earlier in Australia. After Jim Sanders’ “find” on his property near Nevada City in California’s Gold Country made news last year, Australian prospector Murray Cox compared pictures of Sanders’ “Washington Nugget” with “The Orange Roughie” he unearthed near Melbourne in 1987, the San Francisco Chronicle reported. They were an exact match, except the Washington Nugget sold for $460,000 in March and Cox originally sold it for $50,000. Cox contacted Don Kagin, a coin dealer, and mining geologist Fred Holabird, who together auctioned the nugget for Sanders. The two investigated Cox’s claims and determined he was right. “The parties have mutually concluded that the nugget was from Australia,”