Important Modern & Vintage Timepieces...

Hong Kong, Jun 13, 2023

LOT 66


HKD 88,000 - 176,000

EUR 10,300 - 20,600 / CHF 10,000 - 20,000 / USD 11,200 - 22,300

A fine and rare, stainless steel, manual-winding, round-shaped, anti-magnetic to 600 Gauss, chronometer wristwatch with screwed case-back, lapidated lugs, white colour dial with applied radial steel indexes, suspended Arabic numerals and centreseconds; the movement protected inside a soft iron calotte (protective container) against magnetic fields.

Grading System
Grade: AA

Very good

Case: 3


Movement: 3*


Overhaul recommended, at buyer's expense

Dial: 3-53-04




Brand Jaeger-LeCoultre, Le Sentier (Vallée de Joux)

Model “Chronomètre” “Geophysic”

Reference E 168

Year circa 1955

Movement No. 1 276 080

Case No. 748 072 (signed LeCoultre Co.)

Material stainless steel

Buckle stainless steel buckle

Diameter 35 mm. (bezel)

Caliber P 418 / B W Sbr, polished steel index-regulator with swan-neck spring and micrometric screw, adjusted to five positions and temperatures (signed LeCoultre Co.)

Dimensions 43.5 x 35 mm.

Signature dial, case and movement

Accessories repair guarantee certificate


What is Geophysics?

Geophysics, a branch of Earth sciences, is the study of the Earth by quantitative physical methods, especially by seismic, electromagnetic, and radioactivity methods. The theories and techniques of geophysics are employed extensively in the planetary sciences in general.


By the 1950’s the use of electromagnetic motors and nuclear power created a new set of problems for watches – that of stray magnetic fields, which rendered most watches useless. Most “antimagnetic” watches are only rated to 60-80 Gauss and are therefore only suitable for resistance to slightly above normal magnetic fields. Other companies at the same period, released “anti-magnetic” watches. These, however, rarely exceeded a level of resistance to 500 Gauss. They were anti-magnetic due to the beryllium balance and pallet fork combined with an invar balance spring and an “antimagnetic dust cap”. The problem with this is that beryllium contains a small amount of iron in its alloy and is therefore susceptible to magnetism at a certain point. This is also true of the balance spring, which, once magnetized, becomes irregular in shape and duration of pulsation, due to the coils sticking together. The theory behind this is quite brilliant in its simplicity: in much the same way a compass in an iron box does not work as it is shielded from magnetic fields, the movement of the watch continues to work due to the same phenomenon. Similar to a Faraday cage, which conducts stray static charges away from sensitive electronic equipment, the cage in the watch conducts stray magnetic fields away from the movement of the watch. For example, an 8000 Gauss magnet, has a stray magnetic field of 500 Gauss at 6 feet, thus any normal watch will stop functioning properly due to the movement becoming magnetized.