Hi! My name is ***** ***** I would be happy to help with your pretty clock.
The movement and dial were made in Paris, France, by Japy Freres one of the most prolific Parisian clockmakers of the day.
It's not often their clocks are unmarked, but when they are, they can be easily recognized by other features such as the design of the numbers in the chapter ring on the dial, and by the shape and fittings on the backplate of the movement.
These pretty ceramic clock cases were made by many of the Limoges or Paris porcelain manufacturers of the time, that time being circa 1890 - 1910 at the height of the so-called "Belle Epoque" when rococo revival forms such as these scrolling shapes, and decorative motifs -florals and architectural trophée- were all the rage. However, without a maker's mark it's going to be impossible to attribute which factory and/or decorating studio produced it.
The decorative enamel painting and gilding (some of it raised paste gold) is all done by hand and very artfully done.
As for value, as these antique French mantel clocks are primarily decorative rather than functional, the fact it's not in working order won't make any difference to the price. Also, from a clock enthusiast's point of view, this sort of item is considered a welcome restoration project. They prefer to buy "as is" so that they can see exactly what they are getting rather than something that's been 'tinkered with' with possible faults covered up or not immediately obvious.
If you were to see this clock for sale in an antique store it would have a full retail price tag of $750.
I do hope this helps!