I Don’t Believe the Opal Found on Mars has ever been Identified as ‘Precious’

Maybe not, but maybe ….

Opal on Mars

Over the past few weeks, we have seen numerous news reports on the discovery of opal on Mars. Almost every one of these reports is shamefully accompanied by an image, one of Australian Black, Boulder, or White Opal.

The Roskin Gem News Report felt that play-of-color opal is not what they discovered on Mars. So we contacted the Mars opal project to ask them exactly what kind of opal they found.

This is What We Learned

“To my knowledge, I don’t believe the opal-A-rich rocks in Gale crater have ever been identified as ‘precious’ or having play-of-color,” states Travis Gabriel, lead author on “On an Extensive Late Hydrologic Event in Gale Crater as Indicated by Water-Rich Fracture Halos,” found in the Journal of Geophysical Research – Planets, published by the AGU, American Geophysical Union.

The reply from the Mars opal project team was exactly what we expected.

But Can We Cut & Polish It?

Because water is much more important, the opal that has been discovered may not make it to the lapidary. “Understanding the reservoirs of water in the rocks, in the subsurface, in ice, in the atmosphere, etc. can help us better understand how the Martian climate may have evolved over time,” says Albert Yen, one of fifteen authors on this paper, and an expert in Mars mineralogy. “The amorphous silica that we’ve discovered with the Curiosity Mars rover appears to be well-mixed with feldspars and other mineral phases, so the observed deposits are likely insufficiently pure to cut and polish. Further, I believe that the elevated silica deposits that we’ve analyzed formed primarily through acidic leaching of basaltic material, and this process would probably not yield gem-quality opal.”

“However, there is debate on this viewpoint!”

Could it Be?

“There are suggestions that some silica may have migrated in aqueous solutions (at both the Curiosity and Spirit landing sites). If any such silica-rich fluids precipitated with limited impurities, it may be possible that macroscopic samples of relatively pure amorphous silica amenable to cutting and polishing exist on Mars. We just haven’t found anything like this (yet!).”

Hmmm… So maybe, just maybe ….