Unseen since 1957, Mellerio Orléans diamond tiara heads to Sotheby's Geneva sale

A diamond tiara unseen for roughly 69 years will be offered at Sotheby's Geneva Royal and Noble Jewels Sale. The Mellerio Orléans Tiara is a circa-1862 diamond bandeau, a low band worn across the forehead, that converts to a necklace. Sotheby's estimates it at 300,000 to 500,000 Swiss francs.