TIFFANY & CO. 18K YELLOW GOLD OPEN-FACE POCKET WATCH BY PATEK PHILIPPE & CO. , SWITZERLAND,222-jewel movement, no . 171647. Bright-polished case with engraved monogram; white enamel dial has black enamel Arabic numerals; subsidiary seconds dial. - D: 1 3/4 in.; suspended on English 9K yellow gold "endless" chain, L: 30 in. Estimate $1,000-1,500