There’s a word, begins with s, means something like coincidence. Synergy? Sorta kinda not really. Szygy? Awesome word, totally incorrect. Synchronicity. That’s the word. This is synchronicity. Synchronicity has just happened. Because, you see, I wrote a bit about anorthosite and labradorite doing up my geolantern for the Accretionary Wedge, and whilst I was babbling about how totally amazing the mineral labradorite is, I thought that someday, I’d have to get round to photographing my bit of it and write it up. Along came a meme, and it seems someday is today.
Here she is:
I know, right? She doesn’t look all that exciting. You certainly don’t look at her and immediately think, “ZOMG the Moon is made of that stuff!” But it is. Anorthosite is what the lunar highlands are composed of, and anorthosite is predominately labradorite. This makes me want to grab a moon rock, polish it up, and start playing with its labradorescence, but NASA would probably become upset.
(If anybody’s got a bit of anorthosite from the moon that doesn’t belong to NASA and is within the price range of a second-tier cell phone tech support person, do let me know.)
So. We’ve got a rock that has exotic cousins and comes from a pretty exotic locale – I mean, Madagascar, amirite? But it’s just this dark little lump with a hint o’ shimmer. Pretty, but not extraordinary. Why all the fuss? It’s about this time that geologists and rock shop addicts in the audience start grinning that little oh-just-you-wait grin and do something that’ll make your eyes pop.
They tilt the rock, like so:
And you say, “Nope, I still don’t see it.” And they say, “Wait for it,” and tilt just a little bit more. And then, and then
There it comes. Labradorescence. That black rock turns brilliant blue with the flick of a wrist. How gorgeous as that? And it makes me wonder: if we could polish up the Moon, and tilt it just so in the sunlight, could we have a blue moon every night?
Keep tilting, and eventually the whole stone becomes a sea of deep blue fire:
Labradorescence is one thing that makes this mineral so special. You can find an outstanding definition of labradorescence and a fantastic writeup of anorthosite and labradorite at Sandatlas. It can look a bit like opalescence (adularescence), but you’ll see from his description that it’s not quite the same. Those interested in the optical phenomena of various minerals can spend some very happy moments here and here.
The other thing special about it is how very old it is. The anorthosite on the Moon is ancient. On Earth, the youngest you get is from the Proterozoic, so we’re talking nearly a billion years at best. There’s also quite a bit from the Archaen, stretching almost back to the beginning of the planet. Nothing newer that we know of. There are mysteries in this stuff we haven’t solved. And that’s an eye-popping thing to realize about my little bit of rock. It’s not just beautiful, it’s old and strange. Much like another beloved bit of my life:
I believe you can see why I squeed like someone encountering a basket of free kittens when I found this delight at that wonderful little rock shop in Vantage, Washington.
For those of you who like geology and goggies, Garry Hayes has got you covered.
Right. Meme’s live in the geoblogosphere. Getcher labradorite on!