Potassium Permanganate is a dark purple solid. Dissolving 1 ounce in a pint of water is used to stain woods a pleasant brown. The Potassium Permanganate decomposes on contact with the wood and leaves a brown residue that stains the wood. If the color is too dark it can be lightened by washing the wood with a strong solution of hypo. The brown color imparted to fairly woods will gradually fade when exposed to direct sunlight. Mix only enough solution to do the job at hand as the solution on long standing will lose its effectiveness. Use it with caution as it is a strong oxidizer.