MichaelAngelo the 16th centruy 40 year old artist very carefully mixes elements for making oil paint in his apothocary using a mortice and p...

In the times of these famous artists no commercial paint ws available to artists. They preferred to make their own anyway and still do. They had their own formulaes and it was a considered part of the apothacery and alchemy, specifically the process of chrysopoeia or making gold. Blue was considered the most valuable as indigo stone and lapis lazuli were rare from which it was drawn.