The adjacent photo comparison from Tonina, Chiapas, offers sad evidence of how excavated stucco sculpture is rapidly deteriorating at some Maya sites, usually due to disinterest in conservation and an utter lack of thinking ahead. The images are of an important throne in Tonina’s acropolis, decorated with an image of a “star peccary” on its back and with three trident-flint supports. As one can see, much of the sculpted design has now disappeared.
The throne was once inscribed. In 1983 I noticed a stucco glyph (an emblem glyph, in fact) attached to the throne’s right side, but for some reason this was later detached, and eventually published as Plate 89 in Miller and Martin’s book Courtly Art of the Ancient Maya (2004).
I wish this was a unique case of a monument’s destruction-by-excavation, but tragically it’s not; there are many, many more examples out there.