impure chunk of arcane stone is dropped by golems; in nektulos, by patchwork men near -870, 68, -1534 ; they are lvl 29 or 30 and have aggro but they attack one at a time and are not heroic (as long as you pull properly, you can solo them at lvl 28 with a berserker, even with junky armor, I did), they are accompanied by zombies of the same level, so you can do both Legend and Lore quests while you're there ; that's lower level than what this document currently suggests, so that's why I'm posting it.
