The rationalisation of the processes to make medieval pigments and paints are made through the chemical knowledge of the twenty first century. The reproduction is carried out with as much historical accuracy as possible, taking advantage of the shortcuts offered by today’s chemistry, and validated...
and urine to help it adhere to the cave wall. In addition, they used extenders like feldspar and biotite, or ground quartz and calcium phosphate (from crushed animal bone), in order to save on the pigment, to make the paint adhere more firmly to the cave wall and to prevent the paint...