Historical Pigments: Malachite

Malachite is our oldest mineral green pigment, lightfast and reliable, used at least since the third millenium BC. Its name derive from Greek molochitis lithos, “mallow-green stone”. Its coppery nature associates it with the planet Venus.
Other names for the pigment: Mountain green, mineral green.
What it is: A basic copper carbonate hydroxide, chemical formula Cu₂CO₃(OH)₂. Found in copper deposits.
Granulation: Yes. The pigment can be further mulled for a smoother paint film but the colour will get paler.
Compatible with: Egg tempera, egg glair, gum arabic, casein. Performs poorly in oil.
How to use it:
  1. Place a small amount in a palette well or eggcup and add a few drops of water, just enough to wet the pigment into a stiff paste.
  2. Add equal amount of gum arabic solution, or egg tempera, or glair, or casein, and mix well. (Note that gum arabic can be left to dry and then re-wet later. The other mediums are no longer usable once dry.)

Notes:  Malachite is remarkably lightfast, but less stable in the presence of some other pigments, so it is good practice to not admix it. To modify the hue, use thin layers of colour instead.

My hand-ground malachite is available in the shop, while stocks last!

Extraction journal:
The stone, which can be quite hard, is first broken up in a brass mortar, into sand as fine as possible.
Once it’s fine enough, it’s transferred to a ceramic mortar.
The rest of the process consists in washing the powdered malachite to separate it from any impurities in the stone. I add water and grind the powder about, pouring out the pigment as I go and repeating until it’s all been processed.
The containers are left to dry completely.
Finally the dry pigment is collected and ready for use.
My hand-ground malachite is available in the shop, while stocks last.

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