Sergio (carbonado)

A 1906 Popular Science Monthly engraving of the Sergio

The Sergio (Portuguese: Carbonado do Sérgio) was the largest carbonado and the largest rough diamond ever dug up on earth.[1] 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.[2][3][4][5][6][7][8][9][excessive citations]

The Sergio was first sold for $16,000 and later for $25,000 (equivalent to $915,600 in 2023) 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 (equivalent to £933,766 in 2023). It was then broken up into small 3–6-carat (0.60–1.20 g; 0.021–0.042 oz) pieces as industrial diamond drills.[10]

  1. ^ William, Stephen E. (Summer 2017). "Carbonado Diamond: A Review of Properties and Origin". Gemological Institute of America. Retrieved 4 April 2018.
  2. ^ "Carbonado - A possible relic from Uranus or Neptune". meteoritestudies.com. Retrieved 15 February 2013.
  3. ^ Rudler, Frederick William (1911). "Carbonado" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 5 (11th ed.). Cambridge University Press. p. 307.
  4. ^ Broad, William J. (17 September 1996). "Giant Black Diamonds Of Mysterious Origin May Hail From Space". New York Times. Retrieved 4 April 2018.
  5. ^ "Diamonds in the Sky". www.pbs.org. February 2000.
  6. ^ Ralf Tappert, Michelle C. Tappert "Diamonds in Nature: A Guide to Rough Diamonds", p. 41
  7. ^ Mark A. Prelas, Galina Popovici, Louis K. Bigelow (eds.) "Handbook of Industrial Diamonds and Diamond Films", p. 484
  8. ^ G.J.H. McCall, "The carbonado diamond conundrum" Archived 2014-02-21 at the Wayback Machine
  9. ^ 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[dead link‍]
  10. ^ Herold, Marc W. (April 2013). "The Black Diamonds of Bahia (Carbonados) and the Building of Euro-America: A Half-century Supply Monopoly (1880s-1930s)" (PDF). University of New Hampshire. p. 12. Retrieved 4 April 2018.