A JMU professor has unearthed evidence that a meteorite impact created unusual diamond-rich materials in the Sahara Desert 29 million years ago.
Chiara Elmi, a mineralogy professor at JMU, identified traces of mullite, a mineral that forms only under extreme temperatures and pressures, using high-resolution X-ray diffraction instrumentation in her lab.
Previous analyses had not detected mullite in the materials from the Sahara.
Elmi’s expertise in analyzing minerals using X-ray diffraction, including minerals formed by lightning strikes, enabled her to develop an approach for detecting tiny mineral signals that would otherwise go unnoticed.
Scientists have debated the origin of the mysterious Hypatia pebble, an unusual diamond-rich object discovered in the Sahara that has been linked to a possible extraterrestrial source, for decades.
“We were able to find minerals that were not found before because they were hidden in extremely small peaks,” Elmi said. “Mullite is not normally found in nature at ambient conditions. It forms in very high-temperature environments, so finding it was a key piece of evidence.”
Researcher Marco Andreoli, who has spent decades investigating the Sahara’s unusual geology, has described the result as a breakthrough.
Elmi was asked in 2019 to collaborate with Andreoli’s international team, which included researchers from Italy, France, South Africa and the United States.
The study connects the famous Hypatia pebble with evidence of ancient impact-generated melt rocks and high-temperature minerals distributed across a broad area of Egypt’s southwestern desert, offering new insight into one of the most discussed meteorite-related discoveries on Earth.