Here's a bit of disturbing trivia:
There are dozens, maybe hundreds, of paintings hanging in the Louvre and in the Smithsonian collections that contain mummified human remains.
Between the 1500s and the 1800s, there was a bit of a mummy craze in Europe. Mummies were an exotic collectible for the rich and they were also used to make drinks, salves, and paints. For centuries mummified remains were pulled out of the ground in parts of Africa and the Middle East to make “mummia”, a cure-all substance. Once Europe got exposed to it, mummy exportation became an enterprise. It went so extreme that graverobbers started digging up corpses to make their own mummies to meet the demand.
The color made from mummies was a translucent brown, falling somewhere between raw and burnt umber. It's tough to say specifically what paintings and antiques contain mummies. The specific chemical that gave the paint it's pigmentation is bitumen, which can be made in other ways. So it may not be possible to tie the presence of bitumen back to mummies. Liberty Leading the People (pictured below) is a painting that was likely painted using mummy brown. Artists themselves probably didn't realize the origins of their tubes of paint labeled mummy.
If using ground up human remains to make paint sounds like a backwards practice from the past, it may horrify you to know that mummy brown was manufactured well into the 20th century. A New York Times article from 1964 featured an interview with a paint manufacturer about selling off their last mummy.
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