Special relica material

Hello, I'm curious as to when you decide to make some relica in the workshop, when it comes to the screen where you decide how many magic crystals you want to use, I noticed there was a special material part, I was wondering how I could obtain those? Is it like the magic crystals and I need to battle more or are they loot from missions? Are they even obtainable?

They were rewards in a past event.  You can also get them from the divinity battles.  They don't make your relica any better, they only let you control which type is crafted.

Ah, I see, thank you.