A spectacular pink diamond, the largest of its kind to ever appear at auction, sold for $28.5 million (26.6 million euros) on Tuesday, narrowly beating auction house Christie's projection. 

An unidentified bidder snatched up the 16.08-carat rare gemstone, kicking off a week of auctions that could see another colored diamond set a new world record.

That stone, a 12.03-carat blue diamond described by experts as flawless, is being sold by rival auction house Sotheby's on Wednesday, and could fetch a record $55 million.