A massive cheque awaits one mystery woman in Silicon Valley after the old computer she dropped off at a recycling firm ended up selling at an auction for $200,000 (£131,000).

The computer in question is a rare Apple-1 – one of the first pre-assembled Apple computers built by co-founder Steve Wozniak in 1976. When the recycling company CleanBayArea’s vice president Victor Gichun first saw the machine he believed it to be fake, but after being confirmed as the real deal he sold the machine for a huge profit.

But CleanBayArea has a policy whereby it splits any proceeds gained by donated items with the person who brought the item in. As a result, there is now a $100,000 (£65,200) cheque – half of the price paid – waiting for the donator.

So who is the mystery woman? Nobody knows. According to Sky reports, she is believed to be in her 60s, and donated several electronic items in Milpitas, California in April 2015. Mr Gichun confirmed that she told CleanBayArea staff about how she had found the computer parts when cleaning out her garage after the sad news of her husband’s death.

She left no personal details, nor did she fill out a tax receipt for the donations.

Back in 1976 when it was originally released, the Apple-1 was on sale for $666.66 – which after being adjusted for inflation would be the equivalent of around $2,786 (£1,821) today.

It’s not the first Apple-1 in good condition that has been sold at auction. In October 2014 a near-mint condition Apple-1 sold for a whopping $905,000 (£564,000) at a New York auction. Then, in December 2014, another Apple-1 went straight from late Apple founder Steve Job’s garage onto the auction lot. It is the only machine to have been personally sold by Jobs, and went for $365,000 (£230,000).

The hunt continues to reward the mystery donor.