Add Yahoo as a preferred source to see more of our stories on Google. Scientists recently unveiled the nation's newest "oldest known" rock — discovered in Michigan's Upper Peninsula. Michigan, ...

Scientists recently unveiled the nation's newest "oldest known" rock — discovered in Michigan's Upper Peninsula. Michigan, Minnesota and Wisconsin all feature ancient rocks known as gneisses — ...

Metamorphic rocks are more than beautiful patterns in stone—they’re nature’s archives, recording the pressures, temperatures, and forces that shaped our planet over millions of years. From the banded ...

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If you like the deepest and oldest mysteries, find a metamorphic rock. These rocks form deep within the Earth under extreme conditions. Take any rock, subject it to great heat, pressure, or chemical ...

In a recent study, geologists say Michigan is home to the oldest known rock in the nation. Watersmeet gneiss is found in Michigan's Upper Peninsula. Minnesota's Morton gneiss previously held the title ...