Continental Precious Minerals to bulk sample Arkansas diamond

Continental Precious Minerals (ME) of Toronto is ready to begin work on its diamond claims in Arkansas after receiving financial backing for an initial bulk sample test.

After arduous negotiations with 48 separate landowners, Continental has secured mineral rights to three potentially diamond-bearing pipes near the Prairie Creek deposit, 100 miles southwest of Little Rock. Gem-quality diamonds worth an estimated $10 million have been found at Prairie Creek since the turn of the century, including the 40.23 carat “Uncle Sam” stone and the 15.33 “Star of Arkansas.”

Although the area has been long recognized for its diamonds, no one has ever done exploratory drilling to depth, says Continental President Ed Godin. The diamonds that have been recovered all came from within a few inches of the surface from an estimated 260,000 tons of overburden.

Continental intends to sample 10-20-ft deep test pits on a grid pattern across the pipes to determine the quantity and quality of the diamonds. The company is ready to purchase a $2-million, 10-ton-per-hour mill to process the samples. Godin estimates that a 10,000-ton bulk sample and 5,000 carats of diamonds are needed to complete the study, which should take about two years, he says.

Bateman Engineers Inc. has been contracted to manage the property. Bateman is a world-leader in diamond processing technology and will supply the mill for the project. The mill will crush the bulk sample, separate the heavy minerals, then use x-ray fluorescence to identify diamonds in the concentrate. Diamond recovery is expected to be 98%.

The Arkansas deposits have been confirmed to be lamproite, a rock of volcanic origin that extrudes to the surface in diatremes. The diatremes are often shaped like a champagne glass with a narrow neck from depth expanding into a bowl-like deposit near the surface. The Argyll mine in Australia — the world’s largest diamond mine — is also lamproitic.

The three Continental pipes total more than 140 acres and are estimated to contain 25 million tons of lamproite within the first 100 ft. Depending on the shape of the diatremes, a further 100 million tons may be available to 400-ft depth.

Continental is also involved in a joint venture with BP Minerals to investigate several suspected kimberlites in northern Ontario.