NASA’s Perseverance rover has uncovered compelling evidence of ruby-like crystals embedded within rocks on Mars, hinting at the potential for other precious gemstones—including sapphires—across the planet. This discovery, presented at the 57th Lunar and Planetary Science Conference, could reshape our understanding of Martian geology and the conditions under which these minerals form.
The Discovery at Jezero Crater
The findings stem from laser analyses of “float rocks” – dislodged stones found along the rim of a 4-billion-year-old impact crater in Jezero Crater. Using the rover’s SuperCam laser, scientists excited minerals within these rocks, revealing their chemical composition through emitted light wavelengths. Three samples exhibited clear signatures of corundum, the mineral that forms both rubies and sapphires, with the presence of chromium suggesting a ruby-like structure.
However, the crystals are exceptionally small – less than 0.2 millimeters in diameter – making definitive identification challenging. Researchers emphasize that further chemical analysis is needed to confirm if these are true Martian rubies or other corundum variants. As planetary geologist Valerie Payré explains, “The different types of corundum are based on the chemistry…We cannot quantify the amount of chromium…It is thus difficult to conclude whether they are rubies or other types of corundum.”
How Did These Crystals Form?
On Earth, gemstones like rubies and sapphires typically form through intense geological processes involving high heat and pressure from tectonic activity. Mars, however, lacks confirmed plate tectonics, leading scientists to propose an alternative formation mechanism: cosmic impacts. These collisions generate extreme temperatures and pressures capable of creating corundum, along with hydrothermal fluids that could facilitate their growth.
The current evidence suggests that these crystals may have formed under conditions distinct from those on Earth. Their presence in dislodged rocks also complicates the story, as their original context remains unknown. Payré notes, “As of now, the corundum crystals were found in small pebbles that are coming from elsewhere…It is therefore difficult to constrain the full story.”
Implications and Future Research
While the prospect of Martian gemstones isn’t likely to fuel a new jewelry rush (due to their microscopic size), the discovery underscores the planet’s diverse geological history. The presence of corundum adds to the growing list of potential gemstones found on Mars, including quartz and opal. This raises fundamental questions about the Red Planet’s past environmental conditions and the potential for similar mineral formations elsewhere.
Further research, including the retrieval of additional samples from their original source, is crucial to unraveling the full story behind these Martian crystals. The discovery reinforces the idea that Mars is a complex and geologically active world, capable of hosting conditions conducive to the formation of precious stones.
