Michigan Is Home To America’s Oldest Rock; 3.6 Billion Years Old

I'm in a minority of people with not one but two friends who are geology majors (aka rock nerds). It isn't often that I have news that will excite them. But something monumental has taken place in 3.6 billion years in the making that has left the geology community stunned.

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A secret has been uncovered in Michigan's Upper Peninsula, breaking a record that has previously belonged to Minnesota for many years. Minnesota has boasted that it is home to the world's oldest rock for years, even featuring a plaque proudly showcasing it. However, a recent discovery has dethroned the rock as the oldest, with that title now belonging to Michigan.

Who Has The Oldest Rock?

In 1974, the "Morton Gneiss" in the Minnesota River Valley was dated at 3.8 billion years old, and Minnesota quickly erected a sign boldly claiming it was the "World's Oldest Rock." For a time, this was true. However, it may be time for that sign to come down. Not only is it no longer the Earth's oldest rock, but it isn't even America's oldest rock anymore. Tough luck, Minnesota.

READ MORE: Earliest Evidence of Human Life in Michigan Discovered |

Zircon dating puts Canada's Acasta Gneiss at 4 billion years old, stealing the title of Earth's oldest rock. Zircon dating has also found previous estimates of the Morton Gneiss to be inaccurate, with new tests showing it is 3.5 billion years old.

America's Newest Oldest Rock

First reported by Science News, a rock in Michigan's Upper Peninsula known as "Watersmeet Gneiss" is now 3.8 billion years old and the new title holder for "America's Oldest Rock." The rocks are located in the Porcupine Mountains, which isn't surprising considering the region has long been known for its aged minerals and abundance of copper veins.

So, Michigan either needs to start making a plaque for our old rock or steal Minnesota's. Nothing personal, of course.