This is an exceptional and rare three-piece World War I "Trench Art" mantle garniture set, consisting of a central desk clock and two flanking decorative vases. The most remarkable historical feature of this lot is that it brings together authentic artillery shell casings from both sides of the conflict, representing both the Allied forces and the German Empire. The central clock is meticulously crafted from a heavy German shell, clearly stamped on the base with the original markings of the renowned "Patronenfabrik Karlsruhe", dated "JULI 1917", lot "499", and caliber code "St 255". The front is hand-engraved with the inscription "DIXMUDE", commemorating the famous battle fought in Belgium. Complementing the clock, the two side vases are made from legendary French 75mm artillery shells (marked "75 DEC"), dated 1913 and 1917. They feature elegant hand-engraved floral motifs alongside the historic dates "1914" and "1918". The integrated vintage mechanical clock features a classic 24-hour dial layout, marked "Foreign" at the bottom, and its movement is fully accessible from the back. The entire set is in good antique condition, showcasing a stunning, untouched dark and iridescent natural patina on the brass. The clock movement is visually complete but requires servicing or cleaning to be functional, meaning it is sold as a decorative piece or for restoration. This is a unique opportunity for collectors of military history and exclusive WWI memorabilia.