Plowing for Diamonds in Arkansas

Crater of Diamonds State Park is the world’s only diamond-producing site open to the public. On average, two diamonds are found each day at the park.

The state park’s policy is finder-keepers. What park visitors find is theirs to keep.

Diamonds come in all colors of the rainbow. The colors found at the Crater of Diamonds are white, brown, and yellow, in that order.

The search area at the Crater of Diamonds State Park is a 37 ½-acre plowed field, the eroded surface of the eighth largest diamond-bearing deposit in the world in surface area.

Why plow the search field at the diamond mine?

The practice of plowing the diamond field goes back to the earliest days of commercial diamond mining, according to Park Interpreter Margi Jenks.

In the early 1900s miners used a mule team and farming plow to dig trenches. After tourism began in the 1950s, Millar’s Crater of Diamonds used a road grader to turn over the dirt on what is now the north end of the present diamond search area.

Today’s plowing does several good things. First, it fills in any holes that our diamond searchers may have left unfilled. Unfilled holes are a hazard to our visitors, which is the reason that we ask our searchers to fill in their holes at the end of each search day. Filling those holes one-by-one would be time-consuming for our maintenance staff. So, with the blade on the dozer, as we plow the field, we also fill all the holes at one time.

The second, and most important reason to plow, is to turn over the dirt. That ensures searchers are not always looking through the same dirt.

Visitors at Crater of Diamonds look through freshly plowed field.

However, more important is to bring up new lamproite volcanic rock to expose it to the elements. When that exposure happens, the lamproite ash and lava break down and weather to dirt and clay fairly quickly. As the volcanic rocks break down, the diamonds are released from the volcanic materials that hold them, and become mixed with the dirt on the field surface. This weathering characteristic is the reason that our visitors are still finding diamonds after 106 years of searching.

Because the plowing brings up “new” or fresh dirt, many visitors believe that the best time to look for diamonds is just after the field is plowed.

That idea is partially true, but the really great time to look for diamonds is after the field is plowed and followed by a good washing rain. This washes the dirt away on the tops of the plowed rows, leaving diamonds exposed. Or, if the rain water picks up a diamond, the visitors find them in the little areas of gravel and diamonds, which settle out where ever the water slows down.

However, one of the negatives about plowing the field is the process essentially erases the ways that people find the diamonds.

The past two summers after the field was plowed and there wasn’t any rain, were lean months for finding diamonds. Thus, it is not too surprising that the diamond count is low so far this year, and visitors have only found 13 over one carat diamonds.

However, with some good rains, like the four inches on Saturday, October 20, visitors hope that visitors will be back to finding more diamonds in the plowed search area.


Crater of Diamonds State Park

Crater of Diamonds State Park is one of the 52 state parks administered by the State Parks Division of the Arkansas Department of Parks and Tourism.

Search area last plowed:  September 28, 2012

Most recent significant rainstorms: 2 inches on November 11

Total diamonds found in 2012: 464

Operating Hours: Visitor Center/Diamond Discovery Center is open 8 a.m.-5 p.m., extended summer hours

Admission: Adults $7.00, children (age 6-12) $4

Camping: $21-28

Location: From Murfreesboro, take Arkansas 301 and go 2.5 miles southwest to the park

Address: 209 State Park Road, Murfreesboro, AR 71958

Phone: (870) 285-3113


Worth Pondering…
Angels are like diamonds. They can’t be made, you have to find them. Each one is unique.

—Jaclyn Smith

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