[meteorite-list] Geologist Solves Mystery of Rock's Round Hole

[Ron Baalke]

http://www.greatfallstribune.com/apps/pbcs.dll/article?AID=/20050619/NEWS01/506190304/1002

Geologist solves mystery of rock's round hole
By KAREN OGDEN
Great Falls Tribune  (Montana)
June 19, 2005

Sometimes it's the simple stories that strike a chord.

Take that of Roland Ritter, an 88-year-old farmer who found a rock with
a hole in it.

This spring, the Tribune ran a short item on Ritter, who stumbled upon
the mysterious cobble while picking rock from his crop rows.

For more than a year, Ritter had shown the stone to anyone who would
look, in search of answers: Was it pierced by man or Mother Nature?

We invited readers to help.

Some offered theories about the hole. A number came from folks puzzling
over their own mystery stones. One writer, Bubbles Grundstrom of
Columbia Falls, even sent photos of her "holy rock."

Clearly, we needed to expand our investigation.

So the Tribune enlisted the help of Dick Berg, senior research geologist
and museum curator at the Montana Bureau of Mines and Geology in Butte.

In addition to solving the mystery, which we'll get to momentarily, Berg
offered some keen insights into Montanans' fascination with stone.

All that glitters ...

Berg estimates he examines up to 70 rocks a year that are either mailed
or lugged into his lab by their discoverers, from the inveterate rock
hound to the hunter who spied a curious cobble in the woods.

"If someone brings something in, even through I'm busy, I can't turn
them away," Berg said.

Some arrive with dollar signs in their eyes, producing sparkling
"diamonds" or glinting "gold."

Berg gently delivers the bad news, walking them through the identifiers
he uses to analyze a stone.

"Usually people are surprisingly good-natured about it, as long as you
can show them why," he said.

But most of the cobbles lugged into Berg's lab don't appear precious,
just perplexing.

"It's curiosity," he said. "Plain old curiosity. ... People want to know
'What is this? Can you put a name on it? Can you tell me how it was
formed?'"

Many have hauled their treasures great distances.

Berg recalls a woman from Pony, near Butte, who brought in a 50-pound
chunk of rock from her family's old farm in Wisconsin.

The family had long thought it was a meteorite.

Although it wasn't (Berg says he has yet to see someone bring in a real
one), the rock held sentimental value for her.

"People will have had something in the family that becomes more
valuable, passing from one generation to another," he said.

Rudyard mystery solved

Be it a rare crystal formation or a colorful river cobble, Berg said he
always takes time to explain a rock's origins.

"There's often a whole story about where that rock came from," he said.

That brings us back to Roland Ritter's stone.

Once upon a time, far, far away from Ritter's farm, a little sea
creature burrowed a hole in the sand.

It may have fed on tiny organisms in the sand, Berg said. Or perhaps it
tucked into the burrow with just its mouth exposed, catching nutrients
drifting by in the water.

When the creature died, its little burrow filled with sand or mud, which
did not harden as much as the material around it when the sand turned to
sandstone.

The rock's story had just begun.

Along came an ice age and a giant ice sheet, which picked up the stone
as it marched southward, Berg said.

As it traveled along in the ice, the stone rubbed against other rocks
and was worn smooth.

Eventually the earth warmed and the mighty glacier began to melt,
dropping the rock on the Hi-Line where, roughly 16,000 years later,
Roland Ritter stooped over to pick it up.

At some point, either in the ice sheet or sometime before or after, the
soft material inside the sea creature's burrow had worn away to create
the beautiful, symmetrical hole that caught Ritter's eye.

Without a trace

Soon the curious stone was riding around in Ritter's car and acting as
the subject of speculation at the Rudyard senior center.

Ritter entertained the idea that the hole was drilled by a homesteader,
or perhaps Indians hundreds or thousands of years ago.

Small rings inside the hole looked like borings to him.

Upon hearing Berg's theory, he said he was "having a little trouble
believing all that."

"But it's possible," he said.

Ritter said he still wants to think that people made the hole.

But "I don't know how in the world they could do it," he added.

Coincidentally, Berg discovered similar burrows - called "trace fossils"
because no skeletal evidence is left - last month in a sandstone bed
exposed in a road cut 4 miles southwest of Bowman's Corner on Montana 200.

That sandstone, from the Two Medicine Formation, formed 80 million years
ago from sand beds in a sea.

Ritter's rock came from elsewhere, possibly Canada, but to find out
would require a more in-depth analysis, said Berg, who examined Ritter's
rock, as always, free of charge.

Lucky rock

Berg's fascination with rocks began in college, when he signed up for a
geology class.

A Chicago-area native, he planned to major in biology, but the biology
class he wanted that semester was full.

"I had a first-class professor, and that's what makes it," said Berg,
68. "I never looked back."

The general public's fascination with rocks amazes him.

"I don't think they're as curious about the solar system or something
like that as a rock that they find on their ranch or farm or wherever
they find it," Berg said. "I think it's their finding it that makes them
curious."

Bubbles Grundstrom found her "holy rock," similar to Ritter's stone,
underwater near a favorite camping spot along the Stillwater River
northwest of Red Lodge in the early 1970s.

Grundstrom, 67, speculates the hole was formed by water erosion.

She's kept the cobble all these years, through several moves, believing
it's a lucky stone.

"And things have gone well for me, so it must be the rock," she said.

Patience is a virtue

Likewise, Jacquie Heffern, of Great Falls, has a spiritual connection to
rocks.

She sent the Tribune an e-mail about her "holy rock," a pierced chunk of
granite which she found on the River Seine in her native Normandy.

She also has a pebble-like mudstone with holes from Wales.

"I have rocks from Ireland, you name it, everywhere I go," said Heffern,
57. "We just came back from Pennsylvania, and I brought one back from
there."

Heffern's greatest pleasure is the slow, scholarly process of
researching a rock's origin.

"In my spirituality, I find that God speaks through nature," she said.
"In many ways, studying nature, it answers spiritual questions for me
because it's kind of a tedious, patient job. ... You have to be patient
finding out answers to your spiritual questions."

Heffern also looks to rocks for inspiration in her paintings.

"Water dripping from rocks and waterfalls, those are my favorite
subjects," she said. "I am fascinated with rocks. I think that because
they are free and anybody can pick them up and they tell wonderful stories."

Heffern doesn't search for sapphires or other gemstones found in Montana.

"I'm more interested in the story and the beauty of rocks," she said.
"The value in the story they tell is enough value for me."

Her husband, daughter and granddaughters, ages 6 and 9, have caught the
rock bug. The family rarely returns from a hike without rocks in the
back of the car, which sometimes spark debate about who discovered them.

"The ones that I like best are the ones that are so strange that you
wonder how Mother Nature ever did that kind of thing," Heffern said.

She is currently using rocks to build terraces in the garden of her new
home.

"In my lifetime, I have moved tons and tons of rocks," Heffern said. "I
have a bad back to prove it."

Yet on outing after outing - drawn to a sparkle, a glint, a curious
color or shape  curiosity compels her to stoop and pick up one more.