America’s Only Diamond Mine

Arkansas Diamonds
Arkansas Diamonds

Diamonds! The very name invokes a torrid imagination: the lure of fabulous lost fortunes, sunken treasure and the wealth of the mysterious Orient, the fabled legends of Zanidu, all tied to one of man’s most precious possessions. First place in the history of gemstones is accorded to the diamond, as it is certainly the best-known gemstone. Its long and colorful history is linked to virtually every civilized society, and has been for thousands of years.

Even its name is derived from the very quality which makes the stone the prince of gems: the Latin adamantem, in turn derived from the Greek adamas, meaning “invincible.” It is the hardest of all the gemstones, and the hardest material known to man, helping it to have an exceptional brilliance and fire to stand apart above all else.

There are two principle diamond varieties. The most familiar is the single crystal, some of which have a high enough clarity to be cut and polished. The other variety is an aggregate of microscopic crystals fused together, known in the industry as bort when gray or carbonado when black. These constitute the bulk of industrial diamonds. The diamond is a distinct mineralogical species composed of pure carbon, but there are other substances that are pure carbon. Amorphous carbon as in charcoal, lamp black, etc., is the most familiar, such that the carbon atoms make up the substance are arranged in random distribution, and have only very weak attractions (bonds) between them. This forms a very soft substance with no crystal form. The second form of carbon is graphite, in which the carbon atoms are tightly bonded together within hexagonal plates. However, each plate is only weakly attracted to one another. This results in the greasy feeling you get when you rub graphite, because, actually, you are sliding these microscopic plates over and against each other. The third form of pure carbon is the diamond, in which all the carbon atoms are carefully arranged such that their location is precise, like the corners of a cube. The very strong bonding, or attraction between atoms, is present in all directions and makes the substance incredibly hard.

Kimberlite Crystals
Kimberlite Crystals

Man has found diamonds in two types of environments, excluding new research into synthetic stones: the mother rock in which they are formed, and in the sands and gravels in which they were deposits at a time subsequent to their formation. Diamonds occur naturally in a special kind of rock known as a “peridotite,” which is formed at great depths in the earth. When the peridotite is diamond-bearing, and most are not, it is commonly called a “kimberlite.” This rock is not a product of volcanic eruption, as once supposed, despite its resemblance to cylindrical shaped bodies of eroded volcanoes. Diamonds occur in kimberlite along with a wide variety of other semi-precious gemstones including garnets, olivines, micas, enstatites. The diamond-bearing kimberlite of South Africa ordinarily is broken or brecciated and weathers easily into yellowish, bluish or greenish gravelly clay. Hence, the terms “yellow ground,” and “blue ground.” Diamonds are originally found in such peridotites, but because of their extreme hardness and durability, they easily survive weathering and transportation by streams, rivers and glaciers. Often diamonds are recovered in the process of gold panning along with other very heavy minerals. Natural concentrations in this manner have given considerable diamond production for hundreds of years to Brazil, for thousands of years to India, and presently, along the sandy coasts of Southwest Africa.

Even here in the United States diamonds have been periodically found in stream beds and gravel bars. Their concentration has been outlined into three major regions: the Southern Appalachian Mountains, the Great Lakes and the western coastal area of California, Washington and Oregon. Since there is a provinciality to the discoveries, it is naturally assumed that they were transported there by natural means from a presently undiscovered source likely to be in northern Canada. A Canadian source is surely expected for the Great Lakes region, since diamond crystals were discovered associated with glacial deposits. Scientists believe that the glacial deposits were derived from somewhere around the northern Hudson Bay area, but to date no diamond-bearing mother rock has ever been found in that region. As for the Appalachians and the Western areas, the source or sources are even more speculative. Periodotites do occur in these areas, but none have ever had a diamond found in them. Some of the alluvial diamonds found in these areas have been fairly large. For example, a 21.25 carat “Theresa” diamond was found in a glacial deposit at Kohlsville, Wisconsin in 1806. Or, take the “Dewey” diamond of 23.75 carats found in 1855 near Manchester, Virginia. How about the “Punch Jones” gem of 34.46 carats found in 1928 at Peterson, West Virginia? Most large diamonds found are given their own identifying name. Perhaps this, above all else, has sustained the vivid lure associated with this gem throughout history.

Peridotite Crystals
Peridotite Crystals

While it is true that many diamonds have been found, and will continue to be, in the scattered sand and gravel alluvial deposits throughout America, these are in reality but chance findings. The discovery of a diamond is greatly enhanced by working directly with the mother rock in which this priceless gem forms. Such a place exists in North America — only one, and its in southwest Arkansas. The only true diamond mine in the entire continent is located near Murfreesboro in Pike County. Unlike any other diamond mine in the world, this one is open to the public and you can dig your own diamond!

Two areas of diamond-bearing kimberlite have been found. The first, and only one of importance, is called the Prairie Creek Kimberlite. It is located 234 miles south-southwest of the Pike County seat, Murfreesboro. The second area comprises three distinct peridotite outcrops known as the Cimberlite, the American and the Black Lick Prospects. The first two have had a few small diamonds recovered, but the Black Lick is believed to be barren. Only the Prairie Creek is of importance, and herein considered.

The Prairie Creek Peridotite area is roughly triangular in shape and covers approximately 73 acres, but only about 12 acres are unweathered rock. The majority of the deposit is covered with a dark rich topsoil, containing the decomposed and disseminated peridotite in various shades of yellow, green and blue. The decomposition of the peridotite has liberated a wide variety of minerals into the soil: serpentine, phiogopite, olivine, magnetite, perovskite, hematite, quartz, pyrite, diopside, epidote, gem amethyst, peridot, garnet, agate, opal and, of course. diamonds.

The weathered material is derived from the peridotite, which occurs as cemented aggregates of angular fragments called breccias. Extensive deposits of this diamondiferous breccia constitute the principle input for the once economically viable commercial mining operation.

The peridotite pipe was first recognized by geologists in 1842, but detailed investigations into its geology were not commenced until 1888. Its similarity to the renown South African kimberlites was recognized back then, but only hand and knee searching for the elusive gems by the early geologists failed to produce any stones. Interest subsided in the possibility of finding diamonds until the early years of the twentieth century.

John Huddlestone, the original owner of the Prairie Creek land with Sam Reyburn who acquired the land subsequently
John Huddlestone, the original owner of the Prairie Creek land with Sam Reyburn who acquired the land subsequently

On August 8, 1906 an Arkansas farmer named John W. Huddleston plowed up a stone in his turnip patch over the Prairie Creek outcrop. Big John Huddleston first saw the two glints. He scratched the stones with a piece of quartz. Not one mark appeared! He reversed the process and watched the scratch appear on the quartz. Then he used something harder — a carborundum stone used to sharpen his knives, and proceeded to put a groove down the middle. The farmer was familiar with attempts to find diamonds in that vicinity, so it is to his credit that he chose not to ignore the find. One of the stones brought an offer of fifty cents from the local banker, but he wisely waited until a Little Rock expert could identity the stones with certainty. Diamonds of 1.35 and 2.75 carats of considerable value were confirmed by the renown New York gemologist, Dr. George Kunz.

Kunz proclaimed “These are absolutely perfect and are equal to the finest stones found at the Jagersfontain mine of South Africa, or that were ever found in India.” The carat stone was a flawless white beauty; the other a perfectly formed yellow gem, first ever discovered in place in America. Big John went on to find an additional $40,000 worth of gems in his turnip patch!

After the find was confirmed, Huddleston was happy to sell his dirt farm to the newly formed Arkansas Diamond Company for $36,000, a considerable fortune in those days. Better yet, he was retained to work for the company. But, like many of new found wealth, he spent most of his fortune in one magnificent fling, and lived the rest of his life on a dollar a day donated by his fellow citizens.

When the real value of the property and his discovery became public knowledge, it started a diamond rush to Murfreesboro that threatened to take on the proportions of California’s famed ‘49 rush. Prospectors searched many areas in the southwest part of the state, but all to no avail.

Huddleston’s discovery started a chain of events that many men thought nature’s blessing was a curse. Millionaires lost so much money in developing the property that probably would never again look at a single diamond. Hundreds of thousands of dollars have been spent by six mining companies this century, but no operation lasted very long. All the attempts have been shrouded in mystery and bedeviled by abuse. Problems of multi-ownership, crippling lawsuits, lack of funds at critical times, and even rumors of international collusion, closed down every mining attempt. One night three of the ore processing plants simultaneously burned down. Next came the feud between the Mauneys and Millars over who was going to mine the diamonds. “Ole Man Mauney” leased part of his control of the diamond-bearing acres to the Millar family, which proceeded to mine so many gems profitably that the elder Mauney hauled the Millars into court 32 times over four years, and the young Walt Mauney tried to cut litigation costs for his father by taking pot shots with a six-shooter at young Howard Millar. Luckily for both, he could not hit the side of a barn, so to speak.

Prairie Creek Lamproite
Prairie Creek Lamproite

The Millars prepared to expand the mining operation, but fire swept their plant. The upcoming Depression damaged the enterprise and spelled doom for the Arkansas Diamond Company. The company had washed and screened the surface breccia but did not do any underground mining or even attempt any large scale digging. The deepest pit was only 46 feet, but a drill hole was reported to have been down about 130 feet. Production ceased in 1932.

In the early months of World War U the United States Geological Survey did extensive testing from 50 prospect holes in the area in hope of finding a good source of industrial diamonds should the war tie up the South African industry. Only 8.4 carats were found in over 400 tons of kimberlite processed. This was considered disappointingly low by the government geologists, so the government denied the company a crucial loan, and interest in the deposit subsequently waned.

The last sustained attempt at commercial mining was engineered by the late Glenn Martin, the noted World War aircraft manufacturer. Nearly $700,000 was spent by the Martin Corporation in the purchase and lease of several adjoining Prairie Creek properties, the erection of a processing plant and the operation of the mine. The enterprise lasted but a year, from the fall of 1948 to that time the following year. Production was dismal, at least the production reported to the state mining officials — only 246 carats worth less than a thousand dollars. The largest was a 4.5 carat stone amongst the 840 recovered crystals. Almost 90 percent of the stones were small industrial quality under one carat weight. Such a production calculates to 0.16 carats per hundred loads of ore, comparing to the 24.0 carats realized in South Africa’s Premier Mine. Each load equals 16 cubic feet. in other words, production was about one carat to ten tons of processed soil! This production compares with the testing the Millars carried out in 1912. At that time more than 100,000 diamonds were recovered. About 70 percent were classed as industrials and 30 percent as gem grade stock, with less than one percent as crushing bort. Of the gems, about 40 percent were white, 40 percent browns, and 20 percent yellows.

The kimberlite pipe property eventually passed through many hands, including the Diamond Corporation of America, and eventually to the control of Ethel P. Wilkinson of Logansport, Indiana. In 1950 a portion of the Prairie Creek area was opened to the general public as the Diamond Preserve of the United States, and collecting by individuals on the 32 acres was permitted. After payment of a modest fee, searching for diamonds was permitted with the understanding that any diamond up to five carats is yours, but over that weight, a royalty of 25 percent of its rough value was to be paid to the owner of the property. A later owner of the now public attraction was Howard A. Millar, son of one of the previous mine operators.

The General Earth Minerals Corporation, a subsidiary of G.F. Industries, bought the – property in 1969 for $1,100,000, with the intent of exploring the possibilities of commercial mining. Very little was done with the property, though, and it continued to operate as an attraction for “digging your own.” By this time, the property came to be known as the Crater of Diamonds. The royalty system was dropped, and now all that you find is yours to keep.

In 1972 the Arkansas state government purchased the Crater of Diamonds for $750,000, and is now Arkansas’ newest and America’s most unique state park. The state park system purchased slightly over 867 acres, including the 78 acre Prairie Creek peridotite. The Crater remains open to the public under state park supervision. There continues to be a two dollar a day admission and digging fee to search the diamond fields.

Each year thousands of visitors enter the Crater of Diamonds to search. Many spectacular finds have been made since opening to the public. Two of the most famous diamonds found at the mine are the Uncle Sam and the Star of Arkansas. The Uncle Sam, found in 1924, diamond ever found at the mine. It was fashioned by a New York 3ewelry firm into an emerald cut pinkish gem of 14.42 carats, and is presently owned by a Fifth Avenue jewelry company.

The Star of Arkansas was found in 1956 by a Dallas housewife, Mrs. Arthur L. Parker, now residing in Taos, New Mexico. It weighed in the rough at 15.31 carats. The stone was officially appraised 20 years ago at $15,000, but a real market value today would make it well over $100,000, particularly considering its fame and place in the history of American gem deposits. The stone took over three months to cut and polish, resulting in an elongated marquise cut about one and one-eighth inches long and one-quarter inch thick. The finished stone of 8.24 carats has over 100 facets. It was cut by the New York firm of Schenk and Van Haelen, who stated that it was exceedingly difficult to cut. The Star of Arkansas is of superior quality blue-white, and more than eight times the hardness of South African diamonds. Its brilliancy is so overwhelming that photographers cannot use overhead lighting, but must filter the light up from below.

Other large stones, ranging in weight from four carats to more than 30 carats, have been found recently. The Star of Murfreesboro, which weighed 34.25 carats in the rough, was found in March of 1964. The Chief of Caristle, a 13.50 carat gem, was discovered in 1966. A couple of years ago the Gary Moore diamond was found: a perfect golden canary yellow weighing 6.43 carats. How about the Eisenhower diamond, a blue-white gem of perfection weighing 3.11 carats? Early in 1972 a stone was found by a Missouri resident that weighed in excess of six carats. And so the finds continue.

Nobody knows how many diamonds have ever been found at the mine, but estimates range from 100,000 to 200,000 individual stones. Around 30,000 people a year try their luck at searching for the gems, and between 200 and 300 stones are found annually. Many are excellent gem quality and are used in the manufacturing of contemporary designer jewelry.

To get to the Crater of Diamonds State Park take Highway 301 south from Murfreesboro for 2½ miles. A short turnoff into the park is well-posted at this point. The short drive will take you first to the parking lot and the park office. While in the office be sure to go through the small museum to get a first-hand look at the appearance of uncut diamonds. Diamonds from this mine are tinted yellow, brown, pink, blue-white, dead white, as well as the opaque black and brown -gray bort.

In the office one can rent screens for sifting the kimberlitic soil for around 50 cents daily, as well as purchase specially designed hand tools for $3.00. Use of these tools, however, is not absolutely necessary, and you may choose to bring your own equipment.

Adjacent to the mine office is the extensive search area, which after paying the entrance fee, you are permitted to dig for diamonds.

Crater of Diamonds Mine - Murfreesboro Arkansas
Crater of Diamonds Mine – Murfreesboro Arkansas

The Crater of Diamonds mine does not really look like a “mine,” that is, there is no big gaping hole in the ground like, the famous Premier Mine of South Africa. Indeed, this mine appears to be a large plowed farm field. One simply picks a spot and looks for diamonds. Its as simple as that — and it’s all luck. There is no preferred area or more productive zone than the next. Diamonds have been found all over the area, and do not seem to be concentrated together. The search area consists of 74 regularly plowed acres.

Both the past commercial mining and the present individual mining efforts are confined to shallow surface workings, taking advantage of the richness of decomposed material and the ease with which weathered rock is excavated. The initial commercial efforts to wash and disaggregate the ore were very crude. Reasonably, efficient processes using washes to concentrate the heavy minerals and grease tables to separate out the diamonds were not introduced until a couple of decades ago. The remnants of these old mills and their machinery can be seen at several points along the edge of the present mine area. There are small mounds, shallow pits, ditches and the like scattered about as testimony to the marginal diamond mining efforts of the past.

There are several basic approaches to hunting for diamonds at the mine, but most prefer to dig down and screen the gravel. It is best to select a spot along a dry creek bed, gully or base of a hill and dig until a heavier, coarser gravel is reached. This may involve only a three to four foot hole. Fill your bucket with the gravel and wash it at one of the several water troughs located about the property. It may be preferable, though, some think, to dry screen as diamonds are easier to recognize dry. Another approach is to carefully screen the freshly plowed soil. Then again, there is an entirely different approach — one preferred by the “old timers.” Go just after a rain, when the soil is laid open, and a few hours before sunset. Facing west into the sun, walk into that glare, and catch the glint arising from any exposed diamond. Dirt does not cling to a diamond, so they will really stand apart. Search for small, well rounded crystals that are transparent. They will sparkle in the sunlight, despite their greasy appearance. If you have any doubt as to the identification of a stone, bring it to the office for official certification.

Maybe your chance of finding a diamond are one in a hundred, but there are thousands who take that as willing odds, and perhaps only to say, “Well, maybe next time!”