Edouard Koehn unveils the Legacy Moonphase Chronograph

0 0 Friday, 5 September 2025 Edit this post

Swiss independent watch brand Edouard Koehn is expanding its Legacy collection with a new self-winding chronograph featuring a moonphase display, presented in two variations. These models join the Legacy Rattrapante, a timepiece we greatly enjoyed reviewing.

Edouard Koehn Legacy Moonphase Chronograph

Characterised by classical lines and harmonious proportions, the new Legacy Moonphase Chronograph draws inspiration from the brand’s rich heritage, particularly an Edouard Koehn yellow gold pocket watch with perpetual calendar, moon phases, and lunar calendar, created circa 1900.

Edouard Koehn Pocket watch, “Chronometer 1st Quality,” No. 64340 - circa 1900

Initially offered in two dial variations, Dune and Ice Blue, the Legacy Moonphase Chronograph comes in a 40 mm case crafted from 316L stainless steel.

The case measures 14.10 mm in thickness including the two domed “glass-box” and anti-reflective sapphire crystals, or 12.90 mm without them.

The two rectangular pushers at 2 o’clock and 4 o’clock, which control the chronograph functions, are paired with an onion-shaped crown, a signature element of the line.

The dial stands out for its timeless elegance, distinguished by applied Breguet numerals and leaf-shaped hands. A vertical satin finish adds a subtle contemporary touch.

The central chronograph seconds hand, in red or blue depending on the version, is activated by the pusher at 2 o’clock, while the pusher at 4 o’clock resets the chronograph function. The instantaneous 30-minute counter is positioned at 3 o’clock, visually balanced by the running seconds at 9 o’clock.

Seamlessly integrated into the layout, the moonphase and date functions are displayed in the subdial at 6 o’clock.

The moonphase display tracks the principal phases of Earth’s satellite, which completes its orbit in 29 days, 12 hours, 44 minutes, and 2.9 seconds. This cycle, called a lunation, was historically essential for defining the length of a month and structuring early timekeeping.

Rounded to 29.5 days, the lunation is divided into four main phases: first quarter, full moon, last quarter, and new moon. These phases are illustrated on a rotating disc depicting the Moon, mounted on a 59-tooth wheel that advances one step per day to provide an accurate representation of the lunar cycle.

The Legacy Moonphase Chronograph is powered by a self-winding mechanical chronograph movement developed in collaboration with Manufacture Concepto, a specialist in high-end mechanical calibres.

Reflecting the 4 Hz (28,000 vibrations per hour) operating frequency of the movement, the outer minute track is divided into four segments per second, allowing for more precise readings when stopping the chronograph seconds hand.

Equipped with a chronometer-grade regulating organ for exceptional precision and reliability, this 262-component calibre offers a 60-hour power reserve.

Water resistant to 50 metres / 165 feet, the watch is fitted with a Louisiana alligator leather strap, available in various colours and secured by a stainless steel folding clasp.

The Edouard Koehn Legacy Moonphase Chronograph is produced in a limited edition of 50 pieces per dial colour, each individually numbered on the case back. Swiss retail price is CHF 8,900. edouardkoehn.com