Auctions: Yellow diamonds add sparkle to Geneva sales

May is the month of jewel sales at home and abroad

The Allnatt, a fancy vivid yellow diamond of 101.29 carats at Sotheby's, Geneva.

Kashmir sapphires, Burmese rubies, Colombian emeralds and lots and lots of diamonds — what’s not to like? Traditionally this is the month for sales which bring a global audience of very rich buyers to Geneva for eye-watering jewels with all sorts of exotic provenance and stories.

The collections of modern and historic jewellery at sales like these are fascinating.