Lightning Crystals

[Thiol]

Hey all, I've just recently hit 15 on my weaver and I've started making cotton thread, but I've already exhausted my limited supply of lightning crystals from grinding random mobs. Has anyone found a decent place to farm these?

My highest combat class is an 18 THM, but any level will do. That way I'll be able to tell if I can continue farming/working on weaving or if I should just focus more on leveling my combat classes.

Thanks in advance