[Even now, there's never any doubt that she loves blastia...]

They're usually similar. The exact appearance depends on its function, so they could be different sizes or colours.

[After a moment, something she hadn't explained before comes to her.] Oh, yeah...Normally, we'd compress a core partway before adding part of its own formula, and then complete it. That ensures that there's an active, built-in network in the mana. But a light doesn't even need that much.