It is Luna, however, who comes up with their next idea.
"...Hmm, okay, I'm going to need...symbol for water, like, the alchemical one or maybe trigrams but probably the Greek kind, wire - gold, for the associations with purity and perfection, if we have any - I can probably make copper work, if we don't have any stocked or you don't want to lend me any, but, you know, it's gold - and gold's all mystically significant in ways copper isn't while still performing as copper would in the modern paradigm -"
She rummages in her duffel bag, and curses her past self's not having picked up a jewelry-crafting habit. It was absolutely in character, she gave that trait to a character she played; why didn't she - oh. Right. Misogyny.
"Well, I don't seem to have had the luck to come prepared for jewelry-smithing, but either way the plan's the same - get wire, wrap it into an infinity sign, an infinite loop, a constant flowing current...
"...Hm, should I buff the crystal to a sphere and just wire-wrap it, or cleave it to a prism and think like I'm doing induction...
"...Well, cleaving the crystal makes it more appropriateky lasing-medium shaped, and..."
...She references a circuit-diagram cheat-sheet, to double-check something, as she starts to arrange the tools and materials necessary for realizing her idea, and grins. "Definitely going with induction and cleaving the crystal so it's neat, given that alternating current has correspondences, diagrammatically speaking. Plus, there's the associations with induced magnets. And blue-and-gold is just a good color scheme in general, which really can't hurt anything."
(How much can Sylvia help with this, anyway? She's bending the wire to shape, but can she conjure it? Luna isn't sure how much doing this with conjured gold would affect the results, but it's a moot point if Sylvia can't conjure gold at all yet.)
Ooh, and she can use the powdered sulfate (- from cleaving that lumpy, cloudy mess into a neat, shiny prism; she wields her tools just so -) as infill on the symbols of water. There, that's settled, and the ritual is ready...ish.
"...Hmm, actually, maybe I want this to be rotationally symmetric-ish water and fire, depending upon one's point of view...Plasma's a sort of fire that flows like water, after all."
...Yeah, she'll flip one of the triangles around. Circles upon circles upon circles, a ceaseless refinement and alignment.
...Now where can she get some red to mix in and make magenta purple?
...First step, make sure she's not going to set anything on fire by adding fire symbolism. Fire blanket out, goes under the ritual setup preemptively... Missing that would be bad.
"Damn, figuring out where I can get something appropriately red is going to be much more of a pain in my ass, pardon my language; paint is right out, but I don't think anything else is immediately ringing a bell. ...copper? No, but maybe as a backup option given that it sort of works like an RGB schema if you count the rust...
"Honestly, I want it to be gems of some sort. But...
"Oh, hmm, thermite.
"Which I am not going to make, but I believe it's made with rust as in iron oxide.
"Which is at least red-ish.
"Though I didn't think to bring any, so that's probably right out."