The 2.79-carat brown diamond was discovered on 13 September by visitor Raynae Madison and her family, who travelled from Oklahoma to celebrate a family occasion, stopping by to visit the Crater of Diamonds State Park in Arkansas.
The park is the only US diamond mine open to the public, where visitors are allowed to keep what they find. Equipped with a basic beach digging kit and sand sifters purchased from a dollar store, the family chose a site on the northern side of the park's search site.
Madison sifted through several buckets of soil and spotted an oblong, lustrous stone, which experts later confirmed as a 2.79-carat brown diamond. It was named the William Diamond in honour of a relative.
“At first I thought it looked really neat, but I wasn’t sure what it was. I honestly thought it was too big to be a diamond,” Madison said.
The 800-acre Crater of Diamonds State Park attracts more than 100,000 visitors a year on the hunt for diamonds. More than 75,000 stones have been unearthed at the park since the first diamonds were discovered in 1906 by farmer John Huddleston, who owned the land at the time. It was designated as an Arkansas state park in 1972. Park interpreter Emma O'Neal explained that plastic deformation creates brown diamonds at the Crater.
"The process creates structural defects during a diamond's formation or movement in magma. These defects reflect red and green light, combining to make the diamond appear brown,” O'Neal explained.
More than 400 diamonds have been discovered at the park so far this year, including four diamonds exceeding two carats. Earlier this year, a New York woman unearthed a 2.3-carat diamond at the Crater of Diamonds State Park and said it would be used for an engagement ring.
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