Oxidation

When I was a small boy, Condy's Crystals was widely used as a disinfectant.

Then I discovered that I could 'paint' with it on leather!  Almost like watercolors, except only in one color - a very nice neutral brown.  The Potassium Permanganate is a very strong oxidizing agent that turns the leather brown immediately (it will do the same to your skin too).  The stronger your sollution of Potassium Permanganate, the darker it will color the leather.

Just like Vinagroon, this is a chemical stain and is quite permanent.  (There is some suggestion that a mild acid like lemon juice will fade out the browning effect, so I am a bit suspicious that this cover of mine had more contrast when I made it.  Some of the darker shades of brown might have "faded" due to the acidic nature of the leather itself.)

Well, in about 1994 I bound a set of health magazines and picked this design for the cover.  It was done on a split.

You should read up a lot about it, before you use it!  It can be dangerous in contact with the wrong substances.  See More.