Stained Three Ringer . . .

Has anyone ever dug old lead stained like this . . . this is the third bullet/musket ball that I've dug that had staining like this over the oxidation . . . the ground that it was dug from is dark so I don't think its from the soil . . . any ideas?

I have plenty bullets stained. The ones I have dug in pine tree roots seem to get coated with sap at some point of 150 years and a few are really dark.

Its just patina it makes the bullets have character in my opinion.

It's just a layer of hard packed dirt and minerals that have built up over that pretty white patina due to being in the ground for 140+ years.  Nearly every minie and musket ball I dig here in Va has the same buildup