Burial Flag Pole Finial?

Dug this 45 years ago with my whites 5000d in the woods next to a colonial cemetery in Marblehead. Looks like cast bronze. Patina is green with little corrosion and it looked like this this out of ground with only soap and water cleanup. I think it’s a flag finial and it may have flown off the flag pole during a ceremony? The thread appears to be 3/8-16 but it’s square tip, similar to a lead screw thread. Either it fractured during hand tapping or when it was screwed to the metal pole and they used it anyway.. Burials were performed at the cemetery from 1638 to the late 1800’s. 600 revolutionary soldiers are interred there. Any comments on what it is? I’ve kept everything I found since I was given a detector for xmas when I was 12!