For my stack Lead White process I take strips of lead and hand roll them into spirals and place them in small clay pots where they stay suspended above a small amount of vinegar. The pots then are buried beneath mounds of steaming, biologically active horse dung. The chemistry is simple: vapours of acetic acid from the vinegar first corrode the lead creating a coating of lead acetate, then carbonic acid from the warm horse dung converts the white corrosion into lead carbonate that forms into the most beautiful white flakes resembling the delicate paper of a wasps nest. The entire process takes roughly three months depending on season and natures variable influence. Once corrosion has taken place the flakes of white are scraped off and ground beneath water. The remaining paste is washed of impurities then laid out in large trays to dry. Once completely dry it is ground again into linseed oil creating the finished product. The result is a handmade pigment and oil paint that assumes the colour of a warm, creamy white like those in found in Rembrandts paintings.
