Lineage 2 Life Stone drops

Sorry if this was discussed earlier, I couldn't get any hits on the search, and I'm kind a new so I have to ask anyway.
What kinds of mobs drop life stones? I mean, is it like restricted, only in hi level areas, or what? Is there like a breakdown on drop rates of life stones somewhere? By dungeon?

[quote]Sorry if this was discussed earlier, I couldn't get any hits on the search, and I'm kind a new so I have to ask anyway.
What kinds of mobs drop life stones? I mean, is it like restricted, only in hi level areas, or what? Is there like a breakdown on drop rates of life stones somewhere? By dungeon? [/quote]

Depends on the grade. You won't get the good stuff form normal walkover mobs. Check out l2guru.com for more info.