It seems that if you dont do the quest with healing the two guys you cant get that stone. There are 3 stones so far i know. The one from the quest with evelyn and the two guys, the one at the crime scene and the one on the road near the burning road north of the village. I got the one from the crime scene and the one from the road but i checked evelyns corpse but there was no stone so be sure that you guys do the quest with the 2 injured guys!
