Crypto per carat: Sothebyâs to accept bitcoin or ether in diamond auction Sotheyby's auction house and last updated 2021-07-07 16:50:52-04 Sothebyâs will be auctioning off a diamond that is more than 100 carats Friday, and while the large size and clarity rating make it exceptional, it is also making news because the auction house will accept cryptocurrency as a form of payment. The diamond, called Key 10138, âwas named to symbolise the unlocking of a new era in commerce and technology, and thus is a key to history,â the company said. It is expected to go for up to $15 million, and the auction house will accept bitcoin, ether, or traditional forms of money for payment. Sothebyâs says this is the first time something of such size and high value has been available for sale with cryptocurrency.