This extremely rare diamond is the most expensive diamond to date, boasting an intense fancy pink colour. The step cut diamond weighs a huge 24.78cts and was originally owned by jeweller Harry Winston. The diamond was last sold for $46 million in 2010 in Geneva, Switzerland at Sotheby’s auction house. 2. Wittelsbach- Graff Diamond: Sale Price $24.3 million This stunning deep clear blue diamond is cushion cut and weighs a huge 31.06 carats. The diamond originates in Golkonda, South India and has a long history of royal owners. The rare stone was last purchased by Laurence Graff for $24.3 million in 2008. 3. Perfect Pink Diamond: Sale Price $23.2 million Weighing 14.23 carats this absolutely perfect pink step cut diamond was last sold in Hong Kong for $23.2 million. The diamond was discovered in the ancient Indian mines and is the perfect combination of colour, clarity and cut grades, with no secondary colours – like most pink diamonds. 4. Bvlgari Diamond Ring: £15.7 million This two stone ring featuring a fancy blue and white diamond was sold at Christie’s New York auction house a couple of years ago. The ring features the largest triangular shaped fancy blue diamond, which weighs 10.95 carats. 5. Wallis Simpson’s Panther Bracelet: Sale Price $12.4 million This unusual diamond encrusted bracelet was sold in 2010 at Sotheby’s London auction for $12.4 million. The bracelets is set with diamonds, rubies, sapphires and emeralds. 6. Emerald and Diamond Tiara: Sale Price $12.3 million The tiara is made of diamonds and 11 polished Emeralds which weigh 500 carats - selling for $12.3 million in 2011 at Sotheby’s Geneva auction house.