I just got a PM asking about staining antlers with Potassium Permanganate, so I'd thought I'd share with everyone. Now I'm no expert on the subject but this has worked for me so far and I use it on everything from sheds to tine repairs.
First off just follow the directions that come with the powder and wear gloves throughout the entire process.
Take about 1 teaspoon (or more depending on the area that needs staining) of powder and mix with water or alcohol. I've used both, but I get better results using over the counter rubbing alcohol. I just pour enough in to fully dissolve the stain. ***You first timers will be hesitant at this step, but don't worry the antlers won't turn purple!
The stain is a dark purple color after mixing, but it will be brown when done drying. You can use a paintbrush to apply the stain, or just about anything that is handy. I tend to use Q-tips for smaller touch ups on bases or repairs. One very important thing to keep in mind is that the longer you let the mixture set, the darker the stain becomes! So whenever you apply a coat to one antler, you need to do the other side at the same time to keep both at the same color stage.
I do one coat on one side then the other side. By the time the second side is done, I go back and put a second coat on both again. This will give you a rough base coat color. Then let the stain set for about 5-10 minutes and come back with another coat on each, starting at the bases and fading it up as far as you like. Don't get the tips as dark as other areas, makes for easier highlights. Just remember the more coats and the longer you leave the stain, the darker the antlers will be.
After you get somewhere close to the color you are looking for, let them dry for a while. They will be a chalky brownish/orange color at this step. Now come back with a fine steel wool pad and make a light pass over the entire antlers. This will remove the chalky residue. Then continue to use the steel wool to highlight the tips, beams, and bases to produce desired look.
Once you are happy with the look, all you have left is to seal them with something. I use a very light coat of krylon mattee spray. Don't get too carried away with the sealer or they will turn out too glossy looking. That's it! It's not real hard to do, but you might want to practice on an old shed or two before doing something big.
Here are some pictures of sheds that I've done with this process. As you can tell, you can make some lighter/darker, just depends on how you like it! All of these were sheds that were bleached white before starting. Hope this helps some of you out!