here , frak grasps that this is more than simple barter ... understands that it is about gold and precious items which had no special value back then ... barter had been the norm and value was given to things that ensured survival like spears or foodstuff but now he gets it that stones and seemingly trivial things like gold itself or the headdress stolen from a tribal leader , these have a power to enchant people so that he could get , say , a cow to slaughter for just a few gold coins .