I own a copy of a A Wanderer in Paris by E.V. Lucas, dated 1908, in which our intrepid Edwardian cultural explorer encounters in the Musée Carnavalet a "painted life-mask of Voltaire, very horrible". Is it still there, I wondered? Well, it is and it is still horrible.
The label says
Masque de Voltaire
Carton moule en peint au naturel
Don de M Maurice Michon, 1898
inv. S 2072
I haven't managed to discover any more about this delight, but thanks a lot for your gift, Maurice!