I just cleaned up a skull that I had sitting out in the weather for a few years. skull and antlers were faded and dirty. I scrubbed the crud off the antlers and peroxided the skull. To make the antlers look more natural looking I used some darker wood stain. [ black walnut tone I think ] just applying it with a small paint brush and then wiping it while still wet to blend the colors. I'm quite happy with the results.