I found these tags at a field that once had a farm house on it. I was able to date the house through the local historical society to 1853. The first is a dog tag, the second is a tool tag for Bethlehem Ship Yard, the third I a token Alex Grant & Co. Thanks for viewing.
Oh boy . .. that is tricky . . . you risk breaking it . . . . maybe ask the world's leading authority on dog tags . . . . Dr, William Bone . .. he'd know . . . tagman51@att.net