Speaking of pottery glaze, some people were wondering what the binding agent was for the color layer on the
terracotta army in China.
No problem, just make model samples, mixing pigments with either animal glue or glue from free-range chicken eggs, then bury for a year.
2-Extract proteins from the model and historical samples, give them an ultrasonic bath, centrifuge, and collect supernatants.
3-Prevent EDTA interference in the polychrome layers of the historical samples by complexation and dialysis.
4-Hydrolyze extracted proteins with sequencing grade trypsin to generate peptide fragments.
5-Then simply compare peptide mass fingerprints generated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS).
What could be simpler then that, although you might have to borrow a MALDI-TOF-MS from a neighbor, if you don't have one.