Detail of the back of a 16th century oak panel painting. Scored marks like these are sometimes found in the backs, and are made with compasses as rehearsals of motifs that will be painted in the front of the panel. Furthermore in the image, an old "butterfly" of "double dovetail" was put as structural reinforcement of the butt joinery of the boards that form the panel, but these pieces usually bring other problems not only to the structure but also to the paint.
An example of the use of the same 6 petals rosette, as decorative motif, in this case in furniture, in the panels of a Renaissance chest.
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