Octarine

[bloodyrosemccoy]

You know you’re a serious science fiction writer when you find yourself wondering how to look up just what trace impurities in a gemstone would give it an ultraviolet color—so it’d appear colorless to us but be brilliantly shaded to some other species with a different visible spectrum.

Yes, dudes, I take this stuff seriously.

Granted, this may stem from when I was a kid and I would try my damndest to imagine completely new colors. I don’t think it ever quite worked, but I sure did work at it. But it turns out it’s not for lack of wiring, so there’s still hope!

Comments

[agenttrojie.livejournal.com]

Well, scheelite can be cut as a gemstone, from memory; I think it was once used as a diamond substitute. It is commonly colourless (also green, brown, and a few other colours) but shows up as bright sky blue under UV light. I think that would correspond to being seen as sky blue in UV vision because don't they use UV light to show up the markings that bees can see on flowers?

Tungsten and molybdenum both cause UV fluorescence, so they're probably good impurities to start with. If I turn up any more I'll let you know.

As to rocky moons, sure they can be pink. Provided the rock they're made of is pink :) Ours is mostly made of the equivalent of our mantle rock, however, which is things like lherzolites, which are dark greens etc, but I don't see a reason that a moon couldn't be Mars-coloured - it would just need Fe-rich surface rock and, uh, at least trace water vapour in its atmosphere, from memory. But it's not IMpossible.

[padparadscha.livejournal.com]

Thanks! Yeah, scheelite shows up in my book as an "unusual" gemstone because it's too soft to cut. (The book doesn't mention the sky blue part--cool! It doesn't necessarily need to look like any color we might know, either--it may be another color entirely. But I'll definitely write down "tungsten" and "molybdenum" for future reference!)

As for the moon, I considered a surface rock with high iron content, but I'm worried it'd be too orange. The problem is that I'm looking for a seriously pink moon--rose or raspberry color, something taking its first steps along the scale toward purple. I've found minerals the color I want, but trying to figure out if they would work as the surface of an entire moon. I had considered some manganese compounds, which can provide the pink color--but once again, I'm not sure if I could cover a moon with even a thinnish layer with any degree of real probability, since I have no idea how rare they are. (It's possible this moon can be viewed as an interesting rarity, but I still want it in the realm of the possible.) My best possibility, I think, is making the moon's past include some violent volcanic activity.

Or maybe I'm not making any sense. The life of a writer, I guess--you gotta try to be an expert on everything, and it doesn't always work.

[agenttrojie.livejournal.com]

No, you make absolute sense. I'll do some more digging for you as to likely candidates for pink surface rocks. But as it's a moon, I'm guessing no past atmosphere, no hydrosphere? So hydroxides, carbonates etc are probably out? Volcanic activity's probably your best bet. In which case, you could have, say, a rhyolite with a really high K-spar content ...

[padparadscha.livejournal.com]

Ooh, that might work!

I'm thinking it started out with a thin atmosphere which gradually degraded, and there may be some ice that used to be liquid in the deeper crevices, so there could be a certain amount of carbonates or hydroxides.

[agenttrojie.livejournal.com]

I'll get on it when I'm home :D it sounds like fun. But a good moonwide rhyolitic catastrophe could be entertaining ...

[http://users.livejournal.com/_wastrel/]

I'll do some more digging
Was that intentional or incidental?

[agenttrojie.livejournal.com]

Incidental ... but yay, pun :P