Mid 80's ?
They will probably be brass .. Rub the tarnish off them , see how they look , for the most part the metal portion of a shot shell is to aid in the extraction and head spacing ...
I am no brass expert .. Most people would say shoot them. Will be your call in the end ..
Real danger with old shells ( unknown storage history ) is the powder does not have enough power to push the load down the barrel .. That is more important than a bit of pitting ...
I reload 12 gauge slugs, so Already I am considered by some to not be on the side of caution ...