How One Company Controlled the World's Diamonds

A diamond is carbon, the same element as the lead in a pencil. So how did one company turn it into a promise, and what finally loosened its grip? This is the story of De Beers: how it managed the supply, helped shape the story, and what changed when supply escaped and a laboratory arrived. CHAPTERS 0:00 Carbon into a promise 0:28 Why diamonds broke the usual rules 0:52 Kimberley, 1871: from small claims to one company 1:35 The second idea: Oppenheimer, 1926 2:09 Act 2: Make the machine work 3:25 Creating the demand: 1938 and "A diamond is forever" 4:46 Act 3: The machine starts breaking 5:41 Conflict diamonds and the Kimberley Process 6:34 The 2004 and 2008 court cases 7:03 Act 4: The machine meets technology 8:52 Who owns De Beers now 9:33 What we still do not know 9:50 The short version 10:35 Next time: Argentina SOURCES (figures as of 2 October 2026; add links before publishing) De Beers history pages; Encyclopaedia Britannica; Encyclopedia.com (Kimberley 1871, 1888 merger, 1926, 1929, 1930, 1934) Anglo American, "100 years" history page Bain & Company (rough diamond sales through the London channel, early 1990s); MIT Sloan case study; Cabral, NYU Stern paper Edward Jay Epstein, "Have You Ever Tried to Sell a Diamond?", The Atlantic, 1982 (N.W. Ayer's reported 1938-1941 sales figure) US Treasury press release, April 2022 (Alrosa, about 28% of global diamond mining) European Commission decision of 22 February 2006 (De Beers and Alrosa) SIPRI chapter by De Beers' Andrew Bone; World Diamond Council (conflict diamonds, 1999) UN General Assembly press release (Kimberley Process, in force 1 January 2003) US Department of Justice press releases, July 2004 (plea, industrial diamonds, $10 million fine) De Beers press release, 8 May 2025 (Lightbox, lab-grown wholesale prices) Rapaport, January 2026 (one-carat round index, 2025) Anglo American FY2025 results; H1 2026 results (30 July 2026) Government of Botswana statement, 17 July 2026; Bloomberg, via Rapaport, 29 July 2026 This video explains what happened. It is not investment or financial advice. San Decoded explains how money, markets and business really work, through stories. Subscribe for the next one: Argentina. #DeBeers #Diamonds #BusinessHistory #LabGrownDiamonds #SanDecoded