Solve Problems and Perform a Firsthand Investigation

The Chemistry of Art > 1. Pigments in Painting > Solve Problems and Perform a Firsthand Investigation >

Solve problems and perform a firsthand investigation or process information from secondary sources to identify minerals that have been used as pigments and describe their chemical composition with particular reference to pigments available and used in traditional art by Aboriginal people

• Ochre (reds and yellows) colours were due to iron (III) oxide in anhydrous or hydrated form
  • • Red = Fe₂O₃ (anhydrous)
    • Yellow = Fe₂O₃. H₂O (hydrated)Note: Burning drives off the H₂O which produces a red color
    • Brown = FeO(OH) or Limonite

   

• Black pigments consisted of naturally occurring manganese (IV) oxide or charcoal

• • White pigments came from the clay kaolin or calcium carbonate (CaCO₃)