Drawing showing the structure of the wooden carcase of the Mazarin Chest

This figure shows the construction of the wooden substrate of the Mazarin Chest as viewed from the back. Each side of the chest has been made by jointing together two or more boards of wood. These joints are reinforced by cross-grain butterfly keys. The lid is also made from boards jointed together and reinforced with cross-grain butterfly keys. The two ends are braced with wooden cleats approximately 3 cm wide, and the whole is surrounded by a four-part frame, which overhangs the body of the chest on all four sides. The front, back and sides of the chest use finger joints reinforced with wooden pegs.

The framework of front, sides and back are attached to the base using wooden pegs. The bottom of the chest is made from two boards, without cleats or a surrounding frame. Cross-grain butterfly keys were used in an attempt to stabilise original splits in the timber. However, splits reinforced in this way will reoccur unless fluctuations in relative humidity (RH) are minimised. Over the past 400 years, with movement in the original split line restrained by the butterfly key, a new split has formed in line with the top of the butterfly key. Four round feet are attached to the base using round pegs. The top is hinged to the carcase using five hinges. Although no samples have been taken to identify the exact species of coniferous wood used to make the Mazarin Chest, Japanese cypress (hinoki) is the most likely timber to have been employed.