Cullinan Diamond
The world’s largest diamond, Cullinan weighed 3,106 carats when it was discovered in South Africa back in 1905. Three times larger than any other gem-quality diamond that had been discovered, the mine's manager allegedly believed the stone was a fake and threw it out the window. The Cullinan was eventually gifted to King Edward VII, who had it cut into nine principal stones, many of which are now mounted onto the British Crown Jewels.
See also: The Most Expensive Watches And Jewellery Sold At Auctions Through The Years