Hawkeye,
You have it correct but wrong at the same time...
Potassium permanganate is a very strong oxidizer (you can make some fairly strong explosive and incendiary compounds with it....
). When dissolved in water the solution is a very deep royal purple. However, when applied to organic material, it turns the surface of that material various shades of brown....like my little horn surface. I have some maple gunstocks that I stained with it. I built a matching pair of long rifles for my Dad and I when I was a senior in high school. It is not light fast though and the gunstocks are a fair amount lighter now than they were a half century ago. Nitric acid (Aqua Regia in Latin) is also a strong oxidizer....and it has the same effect on organic materials. Hence its use to stain stocks. It can be used alone for a lighter red / brown color or, with dissolved iron in it, a darker brown. The application of heat accelerates the reaction of the acid and / or iron nitrate with the organic compounds in the wood and it is far more light fast than the permanganate. However, the potassium permanganate solution works almost instantly and with no need for heating. The tip of the little horn may fade some over time, but with a light coat of tung oil it will last far, far longer than I will...
