It looks like rock. From a purely scientific perspective, it almost seems like quartz, but. The way it shatters and melts away when dried--it acts like Ice, at the same time. It's strange.

[ unlike jaime, vash didn't grow up around magic, but rather, science--so this was a complete mystery to him. His thoughts a jumble as he tries to put logic where logic just might not work. ]

--Being magic makes the mose sense. Which also sucks, because that's not at all my forte.
Spirit realm waters makes... absolute sense.
It doesn't seem to stick on anything but people, too...

[ ah ]

Maybe it crystalizes when it touches people because we have magic, too? Even if just a little?