A "perfect" white diamond that will go under Sotheby’s hammer in Hong Kong next month, made its first appearance in the city on Thursday, with experts predicting it will easily fetch up to US$35 million.The flawless 118-carat gem, the size of a chicken egg, was unearthed in 2011 in an undisclosed African nation. It is the largest perfect white diamond ever hit the auction block, and Sotheby’s believes it could be an auction-record breaking....MORE