The Vintage Wrist Watch Company has dated this piece to the 1910s.
The watch has a stem-winding movement which is working nicely. The movement is protected by an inner hinged cover.
The watch measures 51mm diameter excluding the winding crown and loop.
It is added as a powder or paste, then fired until it melts or at least softens, and flows or is pushed into the engraved lines in the metal.

There are silver marks inside both of the case backs, the Swiss 800 silver mark and the German crescent and crown silver mark.
Both of the case backs are stamped Niel HF, this is the mark of Huguenin Freres of Le Locle, Switzerland. They were well known jewellers and watch case makers, as well as manufacturers of some of the early Olympic medals. They were one of the most prolific producers of niello cases throughout the Art Nouveau and Art Deco eras.

The case has some unevenness in places. The front cover has a cartouche with the original owner’s initials.
The winding crown pushes in to open the release the front cover. Inside, there is a glass lens which is in good condition.
The dial is signed Helios, a brand name registered by several different watch makers. The dial is in good condition.
The watch comes in a new presentation box.
The Vintage Wrist Watch Company has dated this piece to the 1910s.
Specialists in antique and vintage wrist watches and pocket watches
You can view the stock and full dealer information on the The Vintage Wrist Watch Company Profile Page