Potassium Permanganate (Condys Crystals) has numerous uses in both gardening and elsewhere.

The origin of the chemical and its common name is as follows:

In 1659 a German chemist, J.R. Glauber, fused a mixture of the mineral pyrolusite and potassium carbonate to obtain a material that, when dissolved in water, gave a green solution (potassium manganate) which slowly shifted to violet potassium permanganate and then finally red.