If you want to make this holiday season exceptional, jewelry is one gift idea that is always well-received. Luckily for you, ...

The gem is a carbonado, one of the toughest forms of natural diamond. Black diamonds are usually ... Sotheby's is describing the sale as a "once-in-a-lifetime opportunity to acquire one of the ...

The 555.55 carat black diamond ... the "HEX.com diamond", in reference to the blockchain platform he founded. The gem is a carbonado, which is one of the toughest forms of natural diamond.