This coffer from late 1800 we found in a antique store in Catania, Sicily. It is easy to find old furniture cheap in Sicily.
This one we decied just to clean with some natural soap and water. And then painted with ecological paint to keep the feeling of the coffer. For a more perfect finish just grind it before painting. The front, both short sides and the top we painted twice, but left the backside and inside with just one round of paint. This for sustainable thinking as you do not see those parts anyway.