Sergio (Portuguese: Carbonado do Sérgio) was the largest carbonado and the largest rough diamond ever found.[1] It weighed a gigantic 3,167 carats (633.4 g; 20.36 ozt) and was found above ground in Lençóis (State of Bahia, Brazil) in 1895 by Sérgio Borges de Carvalho. Like other carbonados, it was believed to be of meteoritic origin.[2][3][4][5][6][7][8][9]
Sergio was first sold for $16,000 and later for $25,000 to Joalheria Kahn and Co. and shipped to G. Kahn in Paris, who sold it to I. K. Gulland of London in September 1895 for £6,400. There, it was broken up into small 3–6-carat (0.60–1.20 g; 0.021–0.042 oz) pieces as industrial diamond drills.[10]