The Rolex Daytona, first created in 1963, is a robust mechanical chronograph designed for daily wear, which explains why most models are made of stainless steel while some feature yellow gold. But there is one exceptional piece that is made of white gold, and it’s coming up for sale.

Nicknamed “The Unicorn” because of its almost-intangible nature, this particular Daytona is believed to be the only reference 6265 that is not made of stainless steel or yellow gold. Manufactured in 1970 and delivered to a German retailer the year after, the watch features a white gold case, a black “sigma” dial with white gold indexes and a stainless steel crown. Originally paired with a leather strap, the current owner replaced it with a white gold strap taken from a white gold Oyster Date.

Current owner John Goldberger acquired the watch eight years ago and has now decided to sell it for a good cause. With an estimate of over CHF 3 million, this rare Daytona will be auctioned by Phillips at The Daytona Ultimatum sale on 12 May in Geneva and proceeds from the sale will benefit Children Action.