A few years ago I was searching along the James river in Virginia, close to a US civil war fort.
I found minnie balls, musket balls, uniform buttons with my metal detector, and broken pottery and clay pipes using my "Twin optical scanners" along the river bank.
Just before calling it quits for the day, I recovered an encrusted iron object using my Minelab Sovereign GT in the all metals search mode.
The encrusted object looked like a large old bolt or possible door handle, but like any other piece of trash I recover on a site with a little history, it was taken away for further identification.
I always take my trash home, instead of dropping it back in the hole and covering it back up.
This saves wasting valuable time digging the same trash target, it also helps to cut down on the chances of trash targets masking good targets.
In the case of the crusty and rusty looking bolt from the Virginia field, my choice to take trash home turned out to be the correct call.
The longer encrusted iron piece crumbled off, after I accidentally dropped the encrusted object in a wash basin while rinsing it off.
This US civil war iron canister shot popped out of the other encrusted round end, a sweet sight for sure.
I could have easily thrown this cool civil war relic away when I first recovered it, not knowing what was hidden in the encrusted outer casing.
Previous experiences with finding encrusted gold class rings and Spanish treasure coins has taught me to always take any trash from the site for further inspection.
I should also add that this is the reason why I always prefer to search in all metal at sites that may contain old coins or artifacts.