Juwar can be found in the mines near the conveyor belts. Talk to him and he will ask you to take a pickax to where Bein died. Venture to the bottom of the Lava Caves and place the pickax in the dark cloud at the exact point where Bein died, and return to Juwar to complete the quest. From this point on, you can get the Hero's Pickax from Juwar at any time.