Why Did Old Masters Use Eggs in Oil Paintings?

[Still Waters]

Leonardo da Vinci seems to have taken “put an egg on it” to heart. 

In 15th-century Italy, oil paints largely replaced egg-based tempera paints. But despite the shift, da Vinci and other old masters experimented with paints that mixed egg and oil together. Now, scientists are learning more about why.

In a new study published in the journal Nature Communications, researchers created their own paint recipes to better understand the role of egg yolk on Renaissance canvases.

https://www.smithsonianmag.com/smart-news/why-the-recipe-for-an-old-master-might-include-egg-yolk-180981901/

A holistic view on the role of egg yolk in Old Masters’ oil paints

https://www.nature.com/articles/s41467-023-36859-5

[Piney]

Russian icons were painted with egg tempera and you can identify a KGB fraud (there's a ton of them on the market) by licking it.

 

[Wistman]

In the 'nineties, the Rembrandt Research Project identified egg in the paint film of Rembrandt's pictures.  It was a bit of a revelation at the time, since for centuries artists had been trying to divine the secret recipe that yielded Rembrandt's peaked impastos.