Crater of Diamonds

Crater of Diamonds State Park covers 911 acres near Murfreesboro in Pike County, Arkansas, and is the only diamond-producing site in the world open to the public. Visitors can search a 37-acre plowed field - the eroded surface of an ancient volcanic pipe - and keep any diamonds or gemstones they find, operating under the park's famous 'finders, keepers' policy. Since the state acquired the property in 1972, visitors have found over 33,000 diamonds, including some of significant size and value. The site produces diamonds in a range of colors including white, yellow, brown, and rare pink.

The park's combination of plowed diamond field, forest, and the Little Missouri River corridor supports diverse wildlife for its size. White-tailed deer, wild turkeys, and armadillos inhabit the forested areas. The Little Missouri River supports smallmouth bass, sunfish, and other Ouachita Mountain fish species. Various songbird species including eastern bluebirds, indigo buntings, and various warblers frequent the park. Red-tailed hawks and turkey vultures soar above the open field. Box turtles, five-lined skinks, and various snake species represent the reptile community.

The diamond search field is kept plowed and largely devoid of vegetation, but surrounding park areas support Ouachita Mountain forest communities. Shortleaf pine, loblolly pine, and various oak species dominate the uplands. Bottomland forests along the Little Missouri River include sycamore, sweetgum, and river birch. The plowed field itself can sprout wildflowers and grasses between plowing cycles. The forested areas include understory species typical of the Ouachita region, including American beautyberry, sassafras, and various ferns.

The park sits atop a lamproite volcanic pipe, a rare type of volcanic formation that erupted approximately 95 million years ago during the Cretaceous period. The lamproite magma originated deep in the Earth's mantle, where extreme heat and pressure crystallize carbon into diamonds. As the magma rose rapidly to the surface through a pipe-shaped conduit, it carried diamonds and other minerals from the mantle. The 37-acre plowed field is the eroded surface of this pipe, and erosion continues to bring diamonds to the surface. This is the only known diamond-producing volcanic pipe in the United States, and one of very few in the world open for public prospecting.

The park experiences a humid subtropical climate with hot, humid summers and mild winters. Summer temperatures reach the low to mid-90s Fahrenheit with high humidity, making diamond hunting best during morning hours. Winters are cool with temperatures in the 40s to 50s and occasional freezing weather. Annual rainfall averages about 55 inches, well-distributed throughout the year. Rain actually assists diamond hunting, as freshly washed surfaces reveal stones more easily. Spring and fall offer the most comfortable conditions for spending hours searching the field.

The first diamond was discovered at the site in 1906 by John Huddleston, a farmer plowing his field. The discovery sparked a diamond rush, and various mining operations attempted to commercially extract diamonds over the following decades, though none achieved lasting profitability. The site changed hands multiple times and operated as a private tourist attraction beginning in the 1950s. Major finds include the 40.23-carat Uncle Sam diamond (1924), the largest diamond ever found in the United States. The site's geological significance and public appeal led to its acquisition as a state park.

Arkansas acquired the crater site in 1972 and established Crater of Diamonds State Park, preserving public access to this unique geological feature. The 'finders, keepers' policy was established as the park's cornerstone, allowing anyone who finds a diamond (or other gemstone) in the plowed field to keep it, regardless of size or value. The park periodically plows the search field to bring fresh material to the surface. Notable recent finds include the 8.52-carat Esperanza Diamond in 2015 and the 4.49-carat Caro Avenger diamond in 2020. The park attracts approximately 200,000 visitors annually.

The 37-acre diamond search field is the park's primary attraction, where visitors can search for diamonds and other minerals using various techniques from surface scanning to soil washing at provided water stations. The Diamond Discovery Center museum features exhibits on diamond geology, mining history, and displays of significant finds. A creek trail follows the Little Missouri River through forested areas. The park identifies all finds for visitors free of charge. Staff provide tips on search techniques, and various tools and equipment are available for rent. Beyond diamonds, visitors may find lamproite minerals, jasper, agate, and quartz crystals.

The park offers 47 campsites with water and electric hookups, plus a group camping area. A visitor center, gift shop, and cafe serve day visitors. Water stations and screening shelters are located at the diamond field. The park is located two miles southeast of Murfreesboro on Highway 301. Murfreesboro provides basic services. Hot Springs (approximately 75 miles northeast) and Little Rock (approximately 120 miles northeast) offer additional lodging and services. An entrance fee applies, which includes diamond field access. Seasonal hours vary.

The park manages the unique challenge of balancing public diamond hunting with geological and ecological preservation. The volcanic pipe is a globally significant geological feature, and the regular plowing of the search field is carefully managed to maintain the resource while providing visitor access. Water quality in the Little Missouri River adjacent to the park is monitored. The forested areas surrounding the search field are managed for habitat quality. The park's educational programs about geology, volcanology, and mineralogy provide significant educational value beyond the recreational treasure-hunting experience.