LONDON, ENGLAND, United Kingdom (Reuters) – A rare, pear-shaped, vivid pink diamond will go under the hammer in Geneva next month, where auctioneers expect it to fetch some $38 million. The “Unique Pink,” described by Sotheby’s as “supremely rare and exceptional,” weighs 15.38 carats. “The Gemological Institute of America, the highest body for grading diamonds, have given this stone their highest possible grading, which is vivid pink,” David Bennett, worldwide chairman of Sotheby’s international jewelry […]