There has always been a question of exactly how rich is the 36 acre field of diamonds. To answer this a syndicate of American and South African mining corporations agreeded to
conduct experimental mining of the field beginning in 1992. These results were obtained from the Crater of the Diamonds State Park staff and are as follows:
Phase I of the experimental mining took place in 1992. Phase I was to determine the size and shape of the volcanic pipe (the diamond deposit). Four mining companies were interested in mining the park. They wanted to know that there was enough dirt to mine and that the size of the pipe would be sufficient enough to commercially mine.
Several conservation organizations opposed the testing. After a court battle, the court allowed 55 days of testing. In this time, the contractor spent his time core drilling around the edges of the pipe. After the testing was completed, the results showed that the surface area of the diamond deposit was 80.23 acres with a volume of over 46 million cubic yards above 300 feet. This made the deposit the eighth largest diamond deposit in the world. The testing showed that approximately 79 million tons of possibly diamond productive ore existed in the pipe. All of these findings were positive for the mining companies. They knew there was enough ore to mine. The next step was to determine if there were sufficient numbers of diamonds, and diamonds of sufficient quality to make a profitable commercial mining operation.
Between 1992 and 1996 two of the original four mining companies dropped out. The remaining two companies wanted to remove about 9,000 tons of dirt, process it through a diamond recovery plant and recover the diamonds for grading. Essentially, this is what was done ie. 9,034 tons of dirt was removed from about 14 trenches. These trenches were dug in locations to cover all the geologic areas of the deposit. In addition to recovering diamonds, the mining companies wanted to do additional core drilling to cover areas that they did not have time to drill in 1992.
Phase II recovered 210 diamonds which weighed 47.48 carats. These diamonds were evaluated by an independent New York Diamond Broker. The official results showed that there were plenty of diamonds but not enough to make a profitable commercial mining operation. This has probably ended any question of commercial mining in the park. A state law was passed in 1997 to prevent further testing.
The areas not tested remain for the public to search. Park officials plow the field regularly to expose new earth for
visitors. Nearby residents have made searching for diamonds a family
ritual and make routine trips to this field on the weekends. The best
time to search is after a heavy rain when diamonds can sometimes be seen
on the surface, shining in the sun.
Boots are needed since the soil is muddy. Prospecting tools are
available for rent at the park and park rangers will help identify and
certify any diamonds found. In addition to diamonds; amethyst, agate,
garnet, and jasper are also found here. There are 60 campsites with water and electrical hookups that are open year-round ($13). Good luck and good prospecting! Admission to Mine area is: Adults ($4.50); Children (6-12) $2.00. Crater of the Diamonds State Park, 209 State Park Road,
Murfreesboro, AR 71958 (870) 285-3113. Crater of the Diamonds
Crater of the Diamonds is the only diamond mine in the United
States. The park allows public access to its fields of diamonds
where you can search for and keep all the diamonds you find.
There have been over 70,000 diamonds found at this mine since it opened.
With the largest discoveries being the Uncle Sam (40 carats and the largest
diamond ever unearthed in the United States),
followed by the 34 carats "Star of Murfreesboro", 16-carat "Amarillo Starlight," and the 15 carats "Star of Arkansas".
An average of 600 diamonds are found each year. Some of the largest of which are on display at the Smithsonian Institution in Washington, DC.
