NASA's Perseverance rover has made a surprising discovery on Mars, revealing a treasure trove of corundum, the mineral that forms rubies and sapphires. This find is significant not because of the minerals' value, but because their formation conditions on Mars are enigmatic. The rover's SuperCam TRL analysis identified chromium-bearing corundum in three plagioclase-rich float rocks, with spectral evidence mirroring terrestrial precious gems. This is the first time corundum has been found on Mars, and its presence raises intriguing questions about the planet's geological history.
Corundum formation typically requires high temperatures or tectonic processes, and its presence in plagioclase-rich rocks is surprising. The rocks, named Hampden River, Coffee Cove, and Smiths Harbour, were found on the rim of Jezero Crater, near impact breccias, suggesting a potential link to the colossal impact that formed the crater. The tiny grains of corundum and the presence of chromium atoms replacing aluminum atoms in the rocks further support this theory.
The discovery highlights the need for a Mars sample return mission to obtain core samples from the outcrop where these float rocks originated. By studying these samples on Earth, scientists could conclusively determine the formation process of the corundum and gain a deeper understanding of Mars' history. This find adds to the growing body of evidence that Mars may have once had conditions suitable for the formation of precious minerals, despite its current arid and inhospitable environment.
