About thirty years ago a hunter in west iran where is known by eylamid civilization in chasing a deer found acave which later was called Kalmakareh.inside full by silver vessels from 500 BC.the man after being captured told it was about a truck full of antiques there.
It was so late for Government but they could find some pieces among people and smugglers. A lot of stuffs are now in japan .US.and some else countries museum. I have not seen personally any metal work like those from that cave.even during islamic times.
You can read the story by googlin Kalmakareh cave.
Ali