cannonball help

Hi all, just got back from my 2nd trip magnet fishing and found this in a brook under some trees. It was all covered in layers of rocky silt. I have been trying to find out more about it. It looks like a cannonball and has a faint seamline round the circumference. The top has an indented circle...

This cannonball was found on a small island here on the west coast of BC. There is no history of mining on the island and the ball was found buried in the ground. It has a rich patina and appears old. The ball is 3.5 inches wide and is 5lbs 13 ounces. It is not perfectly round. It appears...

I've been sitting on, (what I'm sure is a 3.inch diameter cannonball) since I first found it as a child in a large open field while playing in the dirt in Milwaukee, WI. How can I find out more information on it? Send a picture with the dimensions? There's about an inch round flat spot on it and...