Pocket watches fitted with blue sapphire jewels are among the rarest creations in fine watchmaking. Only a few examples are known, primarily produced for the American market in the early 20th century.

The most famous example is the “Edward Howard” watch, launched circa 1910 by the Keystone Watch Company in the United States. This extraordinary watch featured blue sapphire jewels, jeweled banking pins, and a free-sprung balance similar to the Gyromax system—well before Patek Philippe introduced its own Gyromax balance. At the time, it was considered a marvel of modern watchmaking. Its retail price was $350, slightly more than the price of a Ford Model T in 1916–1917 ($345).

Inspired by the success of the Edward Howard “Blue Sapphire” watch, Bunde & Upmeyer, an American importer, commissioned several Swiss makers—including Ekegrén, Koehn, and Patek Philippe—to produce similar pieces. Patek Philippe accepted the challenge and produced very few pocket watch with blue sapphire jewels, specially made for the U.S. market.

These watches are exceptionally rare today. Sapphire was more expensive and difficult to work with than synthetic ruby (which became standard after 1902), so only a handful of these special commissions were ever completed. Known surviving examples are usually found in private American collections.

The “blue sapphire” watches represent a unique chapter in horological history, highlighting both technical innovation and the dynamic exchange between Swiss and American watchmaking at the beginning of the 20th century.