A recycling firm in Silicon Valley is attempting to track down a mystery woman who donated a rare Apple 1 computer, seemingly unaware that it was worth $200,000, Digital Spy reports.

California-based CleanBayArea discovered the collector's item in a box of electrical equipment brought in by a woman in her 60s, who had just cleaned out her late husband's garage.

The company is now trying to track down the donator to hand her a cheque for $100,000, as its policy is to split the proceeds 50-50.

"We thought it was fake - it was real," CleanBayArea Vice president Victor Gichun told NBC news. "Tell this lady to please come over to our warehouse in Milpitas again and we'll give her a cheque for $100,000."

The Apple-1 was hand-built by Apple co-founders Steve Jobs and Steve Wozniak, selling for $666.66 each. Only a few dozen of the computers are still in circulation.

First released in 1976, the Apple-1 was Apple's first product. Jobs famously had to sell his VW Microbus and Wozniak his HP-65 calculator for $500 to bankroll the project.