This beautiful Louis XVI style mantel clock is wrought from porphyry set with silvered bronze and ormolu (or gilt bronze) mounts. The clock case is distinctively shaped, formed to resemble a vase. Most interestingly, the clock functions with a cercle tournant movement: the cylindrical dials rotate through 360 degrees while the hand remains motionless.

The clock is raised on a square porphyry base inset to the sides with pierced rinceaux mounts: the front mount formed from silvered bronze and the side mounts from ormolu. Above the base sits an ormolu plinth, formed to resemble a partial fluted column draped with floral garlands. Atop the plinth, above an ormolu waisted socle, sits the vase-form porphyry clock case.

The porphyry clock case is mounted to the front with an ormolu foliate cartouche, from the top of which springs the arrow-form clock hand. The sides of the case are mounted with ormolu twin classical masks, the faces mythological in their grotesque, verdant form. From the masks spring twin scrolled acanthus-leaf form handles, which re-join the vase at the top ormolu shaped lid. The clock dial features two cylinders, one for hours and one for minutes. The hour cylinder is marked with Roman numerals on individual enamel plaques, while the minute cylinder is inscribed with Arabic numeral five-minute marks, also on individual enamel plaques.