One Mystery Solved

I purchased this hardstone cameo set in an archeological revival style gold locket more than a year ago and have been trying to learn more about it ever since. While I have yet to find another that resembles it closely, I now believe the cameo itself is at least 100 years older than the setting. To me, it looks highly similar to the head on this statuette of the Roman Emperor Domitian by the German Baroque lapidary Johann Bernhard Schwarzeburger (also Schwartzenburger):

https://skd-online-collection.skd.museum/Details/Index/219599

This is hardly enough evidence to assert the cameo is by Schwarzeburger or any of his three sons, but in his Biographical Dictionary of Medallists, which includes gem engravers, Leonard Forrer does write that Schwarzeburger 'is noted for his cameos.' An earlier source also says he made 'engraved gems in relief', i.e., cameos. It seems likely this piece, if not by the Schwarzeburgers, is by a contemporary. (If anyone can find an example on the Internet of a Schwartze[n]burger cameo, please send a link. I can find only statuettes of Emperors Domitian, Titus & Vespasian.)

The mystery of his origins remains, but I no longer have to refer to this guy as The Barbarian, the mystery of his identity has finally been solved: he is clearly after the widely reproduced engraving of the Emperor Nero by Italian Baroque artist Antonio Tempesta. Another argument for placing the cameo back to the first half of the 18th century is the choice of this subject. Later in the century neoclassicism took hold; tastemakers began to scorn the Baroque and Rococo.

Antique lockets are often empty. Inside this one? A sepia photograph of a baby.

Afterthought: Why, oh why, didn't I give this the title Finding Nero?