Two locations in the United States have been worked as commercial diamond mines. The first was a mine near Murfreesboro, Arkansas. It was worked as a commercial diamond mine by a succession of operators in the early 1900s but closed because the deposit was subeconomic. Today it is known as the "Crater of Diamonds" and is operated by the State of Arkansas as a tourist "pay-to-dig mine" where anyone can pay a fee, look for diamonds, and keep any that they find. Up to a few hundred carats of diamonds are found there each year.