An Oklahoma City girl has sold a 3.85-carat diamond she found at an Arkansas park for $20,000. Tana Clymer told television station KWTV that she plans to use the money from the recent sale of the yellow diamond to help pay for college. Tana found the diamond last October while hunting for gems with her family at Crater of Diamonds State Park in Murfreesboro, Ark. She says she couldn't believe her good luck and asked her father if she was dreaming. The park is the only diamond-producing site in the US that is open to the public. Other gems discovered at the state park include amethyst, garnet, peridot, jasper, agate, calcite, barite, and quartz. The yellow diamond the teen found is teardrop-shaped and about the size of a jellybean. (More diamond stories.)