Malachite green has been found in Egyptian tomb paintings from over 5000 years ago.
The mineral is found in copper mines alongside its blue cousin Azurite, both being ores of copper carbonate.
It was believed that Malachite could protect against evil spirits and even up to the late 18th century in Germany it was called a Schreckstein or scary stone used to frighten away demons.
To make into a pigment the natural mineral is carefully selected, crushed, ground to a powder, then washed and levigated by swirling in water to separate the green particles just as is done with gold panning. To be useful as a bright green it must be ground coarse, the powder becomes paler and more transparent the more nely it is ground as can be seen here with two examples below.
In ‘The Craftsman’s Handbook’ of the early 15th C, Cennini advises to coarsely powder the pigment ‘for if you were to grind it too much, it would come out a dingy and ashy colour’.
Little used in the Middle Ages, it was an important colour in Rennaisance paintings of the 15th and 16th centuries but slowly lost favour and was replaced by the end of the 18th century with synthetic alternatives.
Painted as egg tempera or watercolor it is a pale green, but mixed with a drying oil it becomes darker and more transparent.