Removing Creek Stain?

[Hoss]

I would leave it alone. That looks like patina to me. I met this kid once that had two spears. Both found in the open on  a small ledge. He described it as almost a handhold for climbing or a small shelf. anyway both were like that one. Heavy patina on one side that was exposed to the elements for thousands of years. The undersides were both less effected.

[rmartin]

I wouldn't touch it. It looks fine too me