Sergio (Portuguese: Carbonado do Sérgio) is the largest carbonado and the largest rough diamond ever found. It weighed 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 is believed to be of meteoritic origin.
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 pieces as industrial diamond drills.
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