Sergio Sergio (Portugees: Carbonado do Sergio) is die grootste carbonado (swart diamant) en die grootste ongesnyde diamant ooit gevind. Dit weeg 3167 karaat (633.4 g) en is gevind in die Staat van Bahia in Brasilië in 1895. Soos ander carbonados is dit glo van meteoriese oorsprong. "Carbonado - A possible relic from Uranus or Neptune" (in Engels). meteoritestudies.com. Geargiveer vanaf die oorspronklike op 30 Oktober 2019. Besoek op 15 Februarie 2013. Giant Black Diamonds Of Mysterious Origin May Hail From Space Diamonds in the Sky Ralf Tappert, Michelle C. Tappert "Diamonds in Nature: A Guide to Rough Diamonds", p. 41 Mark A. Prelas, Galina Popovici, Louis K. Bigelow (eds.) "Handbook of Industrial Diamonds and Diamond Films", p. 484 "G.J.H. McCall, "The carbonado diamond conundrum"" (PDF). Geargiveer vanaf die oorspronklike (PDF) op 21 Februarie 2014. Besoek op 16 Januarie 2018. R.A. Ketcham, "New textural evidence on the origin of carbonado diamond: An example of 3-D petrography using X-ray computed tomography" Geosphere, GES00908.1, first published on August 14, 2013