When a 316.15-carat diamond was discovered in 2005 at De Beers’ Venetia mine, it was christened the Ponahalo (a Sotho word that means vision) by Jonathan Oppenheimer, head of the chairman’s office of De Beers Group. Only special diamonds are bestowed with a name to memorialize their significance over time. Two of the largest stones from this rock?a 102.11-carat and 70.87-carat rectangular-cut diamond?will be offered at Christie’s Jewels: The New York Sale on October 15. It is part of two important jewelry sales that day, which comprise 273 lots and are expect to realize in excess of $35 million. A portion of the proceeds from the sale of the Ponahalo diamonds will be donated to the Diamond Empowerment Fund, a non-profit organization that funds education programs in African countries where diamonds are a natural resource. That same day at Christie’s, the Superb 20th Century Jewels from an American Collection will offer more than 100 lots of signed jewels by all the leading makers of the 20th century including René Boivin, Tiffany & Co., Cartier, Paul Flato, and Van Cleef & Arpels.