Hi
I want to make nothung without using artisans, but having trouble finding ice stones. Do u know where I can farm for ice stones?
I have tried hermit crab grotto.

I believe stones drop randomly from any mobs, and as you already know they drop from chest in some dungeons. So there isn't really an efficient way to grind for a specific stone. Unless I'm wrong then my bad.

In addition to mob drops, I think you can also get them from dissolving certain magatama. I've gotten them from dissolving the "Lord" magatama you get from bargains somewhere around echigo. I rarely dissolve magatama so haven't confirmed it, but if I'm right, it should drop occasionally for all of the lord ..... magatama.