Edward Koehn gold open-face pocket watch, for Tiffany & Co Geneva, Switzerland, No. 86034, circa

Edward Koehn gold open-face pocket watch, for Tiffany & Co Geneva, Switzerland, No. 86034, circa 1915, porcelain Arabic numeral dial marked: TIFFANY & CO, steel hands and sunk seconds; case marked: FOR TIFFANY & CO BY ED KOEHN, SWITZERLAND, 18K, 36034; movement with complete marks and 21-JEWELS, 7-ADJUSTMENTS; movement cover with engraved dedication: RICHARD FROM HIS FATHER AND MOTHER ON HIS 21ST BIRTHDAY, AUGUST 30TH, 1915; overall H2 1/4" W1 3/4", and 59.5g all in