You might try Rit clothes dye. It will color it bone and antler
but, where it is touched and handled it easily comes off. Therefore if you let it soak into the cracks and such and then buff with a greenie pad I think it will still be there in the cracks and around the popcorn. Then sealing with a thined down coat of CA will give it the effect you are looking for.
This particular one
in the pic
was done in layers. I first applied thinned black oil paint and rubbed it in, and the wiped off all access. That is the really dark areas you see on the antler. Then it was buffed with a greenie, the resulting high areas were white. I then treated those areas with Potassium Permanganate, to achieve the brown areas. It was then coated in a thinned CA to seal it up.
I will then size it too fit the knife that it is being used on and I will generally leave
that area white or at least lighter, often I will randomly buff smaller areas through out the whole piece to give it that lighter contrast to the entire piece. The coat of thinned CA give me the opportunity to keep the entire piece from being whitened (
only selected areas are buffed enough to go through the darker brown color)!
That gives a three color contrast and then the whole thing is sealed with a thinned a final coat of CA as the one in the pic had been. That one in the pic has not had the final contrast of the white areas done to it yet but you can kind of get an idea of what it is going to look like!
It is kind of like painting a painting. In a painting the back ground is done first and then you move forward to the areas that the eye focuses on. With this process the higher areas are the ones that get buffed with the greenie pad and depending on what you do to them IE (change color or leave them white that is the contrast area), the sealing of the areas with CA lets you keep from changing the entire piece each time its buffed because the CA protects the lower areas that have already been colored! The piece in the pic was a well bleached shed that had a lot of popcorn and even a few traces of rodent or bird damage, or
character depending how you do the finish!
Potassium Permanganateis almost permanent when used. In fact don't let it touch your bare hands as it is wash and wear, also it tends to burn as it is a powerful oxidizer. It is used for cleaning well water, among one of its many uses. Being an oxidizer it can't be air shipped and has to go ground shipping. You can buy it on ebay in the powder form and they will ship UPS usually.
Hope this is helpful.
