This dressing table mirror also has that feature. Furthermore, Thomas Chippendale worked in mahogany, which this piece is. The wood is wonderfully heavily patinated.
Dark areas from being handled and the natural oils of hands all over, with the warm red mahogany glowing through in places from underneath. With this amount of patination it can easily date it to the Georgian era of the 1700s. The cherry on top is that this dressing table mirror has its original plate. Again patinated and weathered enough to take it back to the 1700s. So it is 100% complete.
Condition is excellent, commensurate with age. An elegant thing, from a more elegant time.Please research and calculate for your country.