Sotheby’s auction house said that’s exactly what happened to one of their clients, and they are now putting the item up for auction.
The owner bought the 26-carat, cushion-shaped, white diamond in the ‘80’s. Not knowing it was worth anything she wore it while shopping and doing her household chores, Nine News reports. “The owner would wear it out shopping, wear it day-to-day. It’s a good-looking ring,” said Jessica Wyndham, head of Sotheby’s London jewellery department. “No-one had any idea it had any intrinsic value at all. The majority of us can’t even begin to dream of owning a diamond that large.”
The diamond is thought to have been cut in the 19th century, when the style was to cut to conserve the weight rather than to make it as sparkly as possible. “This is a one-off windfall, an amazing find.”
The ring will be auctioned off on July 7, and is expected to fetch 350 pounds ($608,000).
This article originally appeared on Starts at 60.