Meteorite used as a doorstop

A meteorite that had been used as a doorstop on a farm in Edmore, central Michigan, has been identified as a valuable extraterrestrial rock. The object, weighing just over ten kilograms, was discovered by geologist Mona Sirbescu from Central Michigan University in 2018.

Meteorite's origin and history

The meteorite fell from the sky in the 1930s on the same farm. The original owner saw it fall with an impressive noise and dug it up the next morning, still warm, at the bottom of a small crater.

Misidentification and use

The dark gray block was kept as a curiosity and stored with tools. When the farm was bought in 1988, the new owner inherited the rock, warned only that it had fallen from the sky. For about thirty years, the stone was used to block the barn door.

Discovery of its true nature

The situation changed when the owner learned that similar fragments are traded for a high price and finally took his stone to Central Michigan University. Sirbescu placed it under an X-ray fluorescence device, which bombards the rock with rays to read its composition, and immediately understood that she was holding an extraordinary specimen.

Scientific confirmation and value

The analysis shows approximately 88% iron and 12% nickel, a typical signature of iron meteorites that are never found in terrestrial rocks. Nickel, very rare on the Earth's surface, acts as an almost infallible celestial marker. To validate the diagnosis, a piece was sent to the Smithsonian in Washington, while geochemist John Wasson at the University of California at Los Angeles refined the measurement.

Significance and future

With its ten kilograms, the block became the sixth largest meteorite recorded in the state. The valuation is dizzying, because the object is worth at least 100,000 dollars. These iron blocks, however, only form a small minority of falls, which sharpens the desire of collectors.

Scientific and cultural importance

If these stones fascinate collectors and researchers alike, it is because they come from the metallic core of asteroids broken in the early days of the solar system, more than four billion years ago. Each block thus offers a piece of planetary core that has fallen freely on Earth.

Ongoing research

Laboratories still measure its exact content in rare elements, which will determine its final value. The Smithsonian and a museum in Maine are already fighting for the right to acquire it, and the owner has promised to give a portion to the university that uncovered the secret of his doorstop.