Mystery Stone Holes

The holes are about 6 inches deep and an inch in diameter. Just a tiny divot in large, sometimes enormous, rocks.

Yet the numbers of them catch one's attention. They cut into more than 50 rocks scattered about the Whetstone Valley in upper eastern South Dakota, but are also found throughout the world in exotic locations like New Zealand and Scotland.

No single stone size hosts these holes, no common elevation, no similar setting. As they far as their purpose goes, they stand as an enigma waiting to be cracked, some code that needs the right code-breaker.

Current attempts to discover their purpose present unclear or even controversial explanations.

A triangular hole about 6 inches deep rests in a large boulder in the Whetstone Valley area. The shape indicates it could be the work of a chisel, and many similar holes exist throughout the region with some variance. Geological Engineer Bill Roggenthen hypothesizes this hole could be natural and thousands of years old, but he cautions he has only seen a photograph. (Photo by Jon Fisher)

Most of the holes show the mark of a human hand. Triangularly cut, they had to be drilled by a tool with a hardened alloy to cut through granite. The natives of the area lacked the technology for such a feat.

Questioning local and official historians throughout the state reveals few answers. Most have never heard of the holes and the few that do had little to mention.

“We haven't come across of any evidence of why they did it or what the use wasŠ nothing that we can say with any concrete proof,” said Historic Preservation Coordinator Stephen Rogers of the State Historical Society.

The Assistant State Archeologist Mike Fosha said he believes the Whetstone Valley holes were the work of a single jack used made by early settlers of the area.

To help build fences and barns or to clear fields, these settlers would use a single jack and a hammer to dig a deep hole into a rock. Then they would pack it with black powder, cover it with mud, and blast it.

Though possible, the theory contains several question-raising holes that should be filled. First, if the rocks are made to be demolished, why are they still there? A few leftovers would be likely if the farmers thought they had enough building supplies. Yet the Whetstone Valley holds more than 50 holes far away from any considerable settlement of the time.

Also, the holes need to be a foot deep or more to leave enough room for the charge and mud packing, said Professor of Geological Engineering Bill Roggenthen of the South Dakota School of Mines and Technology. Most of the holes found in the valley are 6 inches or less.

Perhaps the most curious problem involves the shape of the hole. A single jack leaves a round hole since the settler would turn the jack while hammering, Roggenthen said. Though some of the holes in the area are round, most are triangular.

“If they're truly triangular, well, gee whiz, that's a little different,” Roggenthen said. “Maybe it was done by people who weren't good single jackers. It doesn't seem likely to me,”

If truly man-made, a triangular shape could more readily be made by a chisel. A chisel has the flat edge that can cut a straight hole into a rock.

Yet this idea begs the question of who. A popular rumor posits it could have been done by Medieval Nordic explorers who may have needed mooring stones to tie their ships. Under this theory the water levels would have been much higher 1,000 years ago than today.

This was the theory Judi Rudebusch held for several years. Rudebusch, a Wilmot businesswoman, has spent more than nine years privately investigating the stone holes and cataloging the various stone locations. After investigating the science, she has concluded the mooring stone theory to be improbable.

Geological investigation shows the water levels could not have been so high at that time. Also, an Indian American camp has been dated to about 1200, which would be underwater. Finally, the stones vary too wildly in elevation to be explained by one water level.

“It doesn't make sense,” Rudebusch said. “You've got to use logic and logic tells you that those all can't be for mooring ships.”

Though the evidence eliminates the idea of mooring ships, it does not quite eliminate the idea of early Nordic explorers. Valdimar Samuelsson, a retired airman in Iceland, offers a separate theory.

“In Iceland we have stones with holes,” Samuelsson wrote in an email to the Public Opinion. “I have found some as boundary stones marking farm boundary. They are called the high stone and low stone.”

Holes in stones would have a variety of uses, Samuelsson wrote. Some were mooring stones, but some marked the beginnings and ends of rivers, or marked roads (especially in the winter). Under Medieval Icelandic law, commoners would mark their land by sticking a marking rod into the holes.

Given the Icelander's drive to explore and their sudden disappearance from Greenland, explorers could have traveled as far as the Midwest area, either through Hudson bay or New York state where several stone holes have been found, he said. They could either have been marking their trail or sectioning land off for themselves.

After looking at the GPS coordinates of several notable holes, Samuelsson said he has found a pattern similar to the manner the ancients would section land.

Naturally, a theory like this demands powerful evidence. The notion that Nordic explorers entered the Midwest would change a significant portion of American history.

Though Rudebusch wants to avoid theories before some rigorous scientific dating is performed, she has reason to think the holes might be younger than the American settlement days. She has found a stone with a hole that was also sheered on one side to fit a wall. Unquestionably, it was built in 1899.

When she asked geologist Scott Wolter to compare the weathering of the hole to the settlement cutting, Wolter found that the hole appeared noticeably older than the 1899 cut and younger than the glacial weathering.

Fosha said the assessment of this stone was closer to a personal assessment and needs firmer testing.

Wolter said the microscopic analysis he used was reliable for relative dating and no different than what any other geologist would use without highly technical equipment.

Perhaps a more accurate procedure would solidify the argument. Someone could perform geochemical analysis on the holes for comparison wrote former Professor of Archeology Alan Watchman of Australian National University in an email to Rudebusch. Watchman has achieved fame by dating petroglyphs in South Africa.

Interested scientists could employ electron microscopy with x-ray scanning or luminescence dating to give a more approximate date that could eliminate opposing viewpoints. However, the procedures are both expensive and untried on the stones.

“Really nobody has that kind of money laying around,” Fosha said. “There's not many education programs and things like that that can do that sort of thing.”

It might be possible if a graduate student wanted to make it a research project, Fosha said. Someone from the academic community would need to get government funding, but it would make a good graduate study, he said.

Wolter said this investigation requires immediate attention since it could have serious repercussions on American history. He said he hopes awareness will stir somebody with the resources on to research.

“The more people talking about it, the more we'll eventually get done,” Wolter said.

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