A 22-pound rock that has been used as a doorstop for 30 years has turned out to be a meteorite valued at approximately $100,000. A Central Michigan University professor made the discovery when a man from Grand Rapids convinced her to look at a rock he found to be unique.

Mona Sirbescu, a geology faculty member in earth and atmospheric sciences at CMU says that over the years many people have asked her if rock specimens are valuable meteorites.

"For 18 years, the answer has been categorically 'no' — meteor wrongs, not meteorites," she said with a smile.

Sirbescu says she was hesitant to meet with the man because she has seen so many ordinary rocks that are not meteorites over the years. When they met, she was genuinely surprised when the man pulled a rock out of a bag that she considered to be "very special."

She determined that it was, in fact, a 22-plus pound meteorite, which makes it the sixth-largest recorded find in Michigan. The meteorite is estimated to be worth $100,000.

"It's the most valuable specimen I have ever held in my life, monetarily and scientifically," she said.

The meteorite's owner, who has chosen to remain anonymous, has pledged to give 10% of its value to CMU to be used as funding for students in earth and atmospheric sciences.

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