Charles Frodsham Gold Openface Six-Minute Tourbillon Pocket Watch

Technical characteristics

Type

Tourbillon openface pocket watch

Functions

Six-minute tourbillon, free sprung

Case Diameter

60 mm

Case Material

18K gold, by Harrison Mill Frodsham

Hallmark Date

1906-1907

Serial Number

09190/12127

Movement Maker

Nicole Nielsen

Place recorded

United Kingdom

Maker / attribution

Charles Frodsham & Co.

Design

Visible features

• Open hinged gold case back showing a frosted gilt three-quarter plate movement. • Prominent exposed tourbillon cage with a three-arm bridge. • Movement plate engraved with 'Chas. Frodsham', '09190', '12127', 'AD. Fmsz', and royal warrants, secured with blued screws. • Hallmark visible on the pendant neck beneath the winding crown and bow.

Identity and Casing

This openface pocket watch is catalogued under the dual numbering '09190/12127' and is housed in an 18-karat gold case measuring 60 mm in diameter. The cataloguer attributes the case construction to Harrison Mill Frodsham, son of Charles Frodsham, and lists the piece as hallmarked 1906–1907. Visual inspection of the pendant confirms a hallmark impression situated below the winding crown and bow. While direct observation is limited to the open hinged gold case back displaying the movement, the catalogue reports that the off-white enamel dial was supplied by Frederick Willis. The dial itself and internal cuvette hallmarks are not visible in the provided movement photograph.

Movement Architecture and Tourbillon

The manual-wind movement was supplied by Nicole Nielsen and is equipped with a six-minute tourbillon carriage and a free-sprung balance. The frosted gilt three-quarter plate is visually secured by blued screws and incorporates an exposed tourbillon cage with a three-arm bridge. The plate displays engraved inscriptions including 'Chas. Frodsham', '09190', '12127', royal warrants, and the cryptogram 'AD. Fmsz'. According to the auction essay, this code originated at the Great Exhibition of 1851 as a cipher for the year 1850 based on the letter sequence of 'Frodsham' with 'Z' representing zero, which the firm reserved for its finest timepieces.

Observatory Testing and Archival Records

Accompanying documentation includes a Charles Frodsham & Co. Ltd. Certificate of Origin dated 24 March 2021, confirming that watch number 09190 received a Class A Kew Observatory certificate in 1906 with 84.3 marks ('Especially Good'). Archival entries state that the watch incurred £52 in manufacturing costs and entered company stock in 1907. The auction essay notes that among roughly 66 tourbillons recorded in Charles Frodsham & Co. archives between 1898 and 1934, only four were built with six-minute carriages. The watch is cited in published horological literature, including Vaudrey Mercer's 'The Frodshams' and Reinhard Meis's 'Das Tourbillon'.

Identification

Serial number

09190/12127

Source note

Facts transcribed from the linked source listing or collection record. Attribution and specifications are source-reported and have not been independently authenticated.

Catalogue references

No catalogue numbers recorded. Numbers are only published once transcribed from a verified edition of a standard catalogue — they are never inferred.