The sumptuary orders introduced by Calvin in the late 16th century expressly forbid the manufacture of crosses, chalices or other ‘idolatory’ instruments of worship. Some decades later, and perhaps even in reaction to this period saw a demand for form watches such as this. Although the human skull in miniature as a symbol of death had a long history dating back to the medieval period. This skull is cast with detailed indentations and engravings to the hinged outer and, as was often the case with these types of watches, also has subtle religious motifs on the dial.
With thanks to David Thompson for the help with this footnote
For a similar example see, David Thompson, 'Watches at the British Museum, P.46
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