I picked up an older Ben Pearson bow recently and everything looks good with one exception. There is a patch on one part of the back side of the upper limb. The bow has black glass on back and belly It shoots well, and nothing seems to be changing in this area.

 

 

Is this anything to worry about or is it just cosmetic? If cosmetic, is there anything I can do to make it look better?

Thanks,
Jeff

It looks like it is just the finish. Make sure the wood is still sealed and have fun with it.