This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
SFCashboxSlag. Pictured is lump of silver slag removed from charred cashbox in San Francisco after the Great Earthquake and Fire of The silver coinage melted but due to their higher meltingpoint the nickels retained their details and were embedded in molten metal stray screw was apparently also in the box and was entombed as well