Mister T, the object's finder, asked:
> Found in Northern NJ, near an iron mine, WWI artillery shell? what is it doing there?
Yes, it is an artillery shell and it appears to be a World War One version, which had a detachable nose, for loading it full of lead antipersonnel (shrapnel) balls.
Explanation of how it came to be found in New Jersey, and unfired, and missing its fuze and antipersonnel balls:
Most people alive today seem to forget that all the way up into the 1950s, the VAST majority of the land in nearly every US state was basically unoccupied. Most land consisted of multi-acre farmfields and undeveloped forests. So, the US Army was free to conduct training and even "live fire" artillery practice almost wherever it wanted to. This is why the James River bluffs below Richmond VA and even Georgia's Kennesaw Mountain and Chickamauga battlefield parks are loaded with fired WW1 and WW2 artillery shells. I suspect your New Jersey WW1 antipersonnel shell was abandoned when "out in the farmfields" training ended at the war's close, and some soldier decided to salvage the hundreds of lead balls inside it. He then discarded its valueless steel body.