616ct Diamond - the world's largest octahedron
四月 26, 2024by John Jeffay
“It's 50 years since the world's largest octahedral diamond was recovered, and even today it remains uncut, unpolished and unsold.
The 616-carat Type 1 yellow diamond, dates back to 17 April 1974 and comes from the Dutoitspan Mine in Kimberley, South Africa, which opened in the 1870s and closed in 2005.
The miner who found the diamond, De Beers employee Abel Maretela, was rewarded with a large bonus and a house.
Al Cook, De Beers Group CEO, was shown the diamond on a visit to Johannesburg, by Moses Madondo, CEO of De Beers Group managed operations.
"I'm a geologist so I love to learn about the history of diamonds even before they were found," he said in a LinkedIn post.
"This is a Type 1 diamond which means that it was formed around 150 km below the earth's surface, deep in the mantle, over 1 billion years ago.
"During the Cretaceous period, about 100 million years ago, a kimberlite volcano brought this diamond up to the earth's surface. Its beautiful yellow colour comes from nitrogen atoms that were trapped inside the carbon lattice when it was forming in the mantle."”
SOURCE: www.idexonline.com
Pictures courtesy of De Beers.