A rare pear-shaped diamond that is expected to fetch up to $15 million can be bought at auction next month using cryptocurrencies, Sotheby’s announced on Monday. Sotheby’s said it would be first time a diamond of such size has been offered for public purchase with cryptocurrency. No other physical object of such high value has previously been available for sale with cryptocurrency, the auction house added. The 101.38-carat pear shaped flawless diamond, dubbed The Key 10138, is one of just ten diamonds of more than 100 carats ever to come to auction, only two of which were pear-shaped. It carries a pre-sale estimate of $10 million–$15 million and will be sold on July 9 in Hong Kong. Bitcoin or ether, along with traditional money, will be accepted as payment. “This is a truly symbolic moment. The most ancient and emblematic denominator of value can now, for the first time, be …