I’d been there many times before, mostly with groups of Mayo or John Marshall High School Environmental Awareness students we took to northern Minnesota for an experience in the Boundary Waters. But, our first day usually involved a hike to Carlton Peak, a rocky outcrop just inland from Lake Superior.

Carlton Peak offers some of the premier rock climbing sites in the Midwest, thus a great field trip for students who got climbing experience and skills in the EA classes, with only soft limestone to climb in southeastern Minnesota. At more than 1,500-foot elevation, almost a thousand feet above Lake Superior, this monolith is an impressive site from afar, also offering spectacular views of its surroundings, including Lake Superior, from atop.

Although the trips I took students on were decades ago, today’s students still get this opportunity with current EA classes. And Carlton Peak has not changed much in that time, since it is made up of a rock that formed deep in the Earth from minerals that made the rock hard enough to withstand degradation over eons of time. I recall it being called anorthosite, but did not know much about its geology, nor the impact it would have on Minnesota’s economy, environment, and charitable giving for more than a hundred years.

Stone cold

That all changed with our family trip to the North Shore this past summer, where my geologist daughter, Jenna, clued me in. Not only did Jenna provide the geological information about anorthosite, but also noted it was responsible for the start-up of one of Minnesota largest companies in 1902.

It was that year that five men founded a business, based in Two Harbors, called Minnesota Mining and Manufacturing (later 3M). They mined an area rock they thought was corundum to make abrasives for grinding wheels, sandpaper, and other industrial products. But the rock they mined from Carlton Peak and other land they purchased created a "conundrum," because it was not corundum, but instead anorthosite, almost worthless for the intended use.

Anorthosite Rocks.  Photo:  Greg Munson

Although the company’s stock reeled from this errant discovery, one of its investors, Lucius Ordway, today a well-known Minnesota name, bailed out the company and became the majority stockholder. By 1909, using imported rock sent the company on the road to success, and allowed Ordway to move 3M's headquarters to St. Paul.

Shortly thereafter, two young Duluth business school grads, William McKnight and A.G. Bush, were hired at the Duluth 3M operation. Although starting in entry-level positions, they both became key figures in the company’s growth and prosperity. And, due to their success at 3M, the names of both those men have carried on in charitable foundations that have given billions away over the past century.

Following its success with sandpaper, 3M became a household name with the 1925 invention of Scotch Tape by engineer Richard Drew, followed by his invention of masking tape in 1930. Later came Post-It Notes, and Thinsulate for insulating clothing, or gloves, soon making 3M a big business in Minnesota, across the U.S., and in more than 60 countries.

Chemical contamination

But, 3M success has also been marred by some of the products they made such as Teflon, Scotch Guard, firefighting foam, and outdoor equipment. These products produced large amounts of waste chemicals called PFCAs, with the same enduring qualities as some of the products they produced, meaning they didn’t degrade easily in the natural environment. The waste PFCAs often seeped into groundwater or went directly into streams and rivers, including the Mississippi.

Concerns about these chemicals reached its peak in Minnesota only a few years ago in Cottage Grove, home to a sprawling 3M facility on the banks of the Mississippi. Small amounts of the PFCAs were found in the blood of area residents as well as Mississippi River fish. A long-term investigation by the state led to a $5 billion suit against 3M, which was settled before trial with an $850 million award from 3M.

Studies for the most part did not appear to indicate human health problems from the 3M chemicals, but perhaps environmental damage. And, while this award caused litigation against 3M in Minnesota to decline, it only opened a groundswell of similar activity in other states, which are now taking place.

So, the anorthosite rock I climbed on with students started a chain reaction of events in Minnesota which greatly impacted the state. Fortunately, most of the land purchased by 3M for mining northosite, including Carlton Peak, has been added to North Shore state parks.

So, if ever on the North Shore, and up for a hike, head to the top of Carlton Peak for a great view.

To read the original article and read related reporting, follow this link to the Post-Bulletin website.  https://www.postbulletin.com/life/lifestyles/m-wasn-t-built-on-this-rock-but-despite-it/article_c0da...