David Anderson discovered the sparkler at the Crater of Diamonds State Park, which invites the public to visit and find the pricey stones.
The park, which is situated in Murfreesboro in Arkansas, US, is the world's only diamond producing site open to the public.
For just $7 (just over £4), hunters can head down to the park and dig away – keeping whatever goodies that they find.
The 6.10 carat David found is the 15th largest diamond to be found at the park, and although it is worth thousands, it's only the size of a jelly bean!
But instead of making some dosh, David plans to sell the gem and give the money to charity. What a diamond!
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