HENDERSON — Forensic geologist Scott Wolter’s job is searching for clues in damaged concrete and stone to provide reports and expert testimony in cases over failed structures.

For the past seven years, his passion has been getting out the word that Minnesota’s Kensington Rune Stone is undeniably real and proves that Scandinavians were in America more than a century before Columbus.

“I understand the difference between fact and speculation. The geology told me this is not a hoax,” Wolter told about 100 people who listened to his presentation Sunday at the Ney Nature Center.

The 202-pound engraved stone was found entangled in a poplar tree root by farmer Olof Ohman in 1898 on his farm near Kensington, located west of Alexandria.

The stone was almost immediately declared a hoax by leading Swedish language scholars who said some of the language and symbols used were too modern.

But Wolter said the attacks on the rune’s authenticity are fatally flawed.

That’s because the scholars at the time were studying a hand-written copy of the rune symbols Ohman had made. Ohman, Wolter said, failed to include subtle notations on the copy, such as two small dots above an “a” in the word “har.” The word “har” is a modern spelling but with the two dots it is right for medieval times.

Wolter argued that if Ohman was sophisticated enough to plan the hoax by carving the rune with the correct medieval language he certainly would have included the correct symbols in the copy he printed for scholars to review.

But Wolter said the most compelling case for authenticity is that the few geology studies of the stone show it is real. The Minnesota state geologist, in 1910, determined that it was real. Wolter’s own geologic study of the stone in 2000, using a host of modern tests and equipment, proves it even more conclusively, he said.

Using a variety of high-tech equipment and comparison samples from the same kind of stone from old grave-markers, Wolter found the edge of the rune stone that had been chiseled off has wear that dates at least to the 1600s, centuries before Ohman was born.

After releasing his findings, Wolter was attacked by critics of the stone who say he was not an expert on the language on the stone that had been questioned. But Wolter said that once the geology was proven, the age of the language had to be authentic.

“So I spent the next seven years learning everything there was to know about runology.”

He and a colleague, Texas engineer Dick Nielsen, spent more than two years going through every page of information on the rune stone held by the Minnesota Historical Society, traveled to Scandinavia several times, and gained access to boxes of Ohman family papers.

He said information proving the language on the stone is indeed medieval was stored away in archives and elsewhere, but that no one had bothered to thoroughly research it.

“No one bothered to look too hard. If it was an obvious hoax, why would you?”

In several old churches on the Scandinavian island of Gotland, Wolter found rune symbols known to be from medieval times that matched the rune symbols on the Kensington stone that critics had argued were too modern.

Wolter said the geologic evidence of the stone’s authenticity is now buttressed by the new runology evidence. But, said Wolter, more than a century’s worth of criticism of the stone by several scholars makes it difficult to change minds easily or quickly.

A fact, he said, that is preventing Minnesota from embracing a major artifact that changes the very history of who discovered America and when.

Wolter has written a book on his findings: “The Kensington Rune Stone, Compelling New Evidence. (www.kensingtonrunestone.com).