I'm a big fan of opals, have been ever since I was a junior rockhound in the Mojave Desert as a child.
And I'm a big fan of Maggie Koerth-Baker, the best science writer around.
So, what could be better than a story by Maggie Koerth-Baker about opals: The Opal's Fire.
Scientists know what makes the difference between precious opal, common opal, and regular silica. But why those differences exist is kind of a mystery. A new theory has an answer for that, while simultaneously explaining why most of the precious opals in the world come from a single place. The solution depends on one surprising fact. Turns out, Central Australia has a lot in common with the surface of Mars.
One thing is clear (besides the fact that opals make pretty jewelry): the next time I visit Mars, I'm bringing my old rock pick.