A product so small that it takes hundreds to cover the face of a penny is a billion-dollar industry in North Dakota’s oil patch.

Research into clay deposits in Dunn and Stark counties could lead to the local manufacture of ceramic “bead” proppants, a product used in hydraulic fracturing, or fracking, and now imported from other states and China.

Oil companies inject millions of pounds of ceramic beads or sand particles into each oil well to prop open the fractures necessary so oil can flow in the deep and very dense formations.

State Geologist Ed Murphy said oil drillers spend anywhere from $500,000 to $1.5 million on proppant material for every well, making it an attractive possibility on the manufacturing side.

“We’ve had interest from the industry all along and as far as I can tell, they’re still looking at it,” Murphy said.

The North Dakota Geological Survey looked at 60 clay samples last year and was encouraged enough to commission the North Dakota State University Center for Nanoscale Science and Engineering minerals laboratory to conduct a larger study of 200 samples.

The center released initial findings last week that were somewhat less promising than the Geological Survey’s first results, but still encouraging for the ceramic industry.

Overall, the center is finding a smaller percentage of alumina in the clay than in the first sampling.

Murphy said ideally, the alumina in the clay — a property that yields a light weight and strength to the ceramic product — is in the mid-30s percentile. Instead, the samplings are finding alumina is closer to 20 percent, but Murphy said chemical additives can make up the difference.

Some clay deposits in the two counties have higher alumina content than others and a map will help companies explore and decide, he said.

“These results are lower than our preliminary results, but we still have a number of sites that (alumina) averages in the mid-20 percent. That’s certainly encouraging enough, based on conversations with the industry,” Murphy said.

Smectite levels

Further tests at the NDSU lab will gauge the amount of smectite in the clay samples. Smectite is a bad-actor mineral that makes clay swell when it’s baked.

“It loses its strength, which is why the Hebron Brick Co. doesn’t want it (smectite clay),” Murphy said.

The center’s final laboratory report is due late this year or early next year.

Even though more than 7,600 oil wells are already producing in North Dakota, the drilling and fracking industries are expected to be around for the 20 or so more years it will take to get to the expected 40,000 wells.

It takes 3 million pounds of ceramic beads per well at 50 cents a pound, or 5 million pounds of sand at

10 cents a pound, to frack each well. Murphy said oil companies prefer one product or the other, based on their own petroleum engineering.

Reach reporter Lauren Donovan at 701-220-5511 or lauren@westriv.com.