Activity Susy Quinn posted a new specimen in the group What is it? from the myFOSSIL app 1 year, 3 months ago 1 year, 3 months ago 1 year, 3 months ago Susy Quinn has contributed a new specimen to myFOSSIL! Gloria Carr replied 1 year, 3 months ago Hi! your best bet is to use a dremel or airscribe. While a vinegar bath can dissolve the sandstone it will also dissolve the fossil shell, so your only option is mechanical removal.