Hello Mr. Al Patrick Boudreaux, Thank you for sending in this most interesting wristwatch to mearto.com for an appraisal. I shall help you with that tonight. TITLE: Gent’s 18k yellow gold, manually wound, mechanical, ultra-thin wristwatch with black alligator strap and gold buckle, S/N 3666, Ref. 15206-0118, made by Bouchet-Lassale Watch Company, Geneva, Switzerland, circa 1976-1979. DESCRIPTION: Case: 25mm x 30mm rectangular, two leaf, 18k yellow gold, mechanical wristwatch with an ultra-thin movement measuring only 1.2mm in depth. The rectangular brushed solid gold case has a rectangular gold bezel with the fluted winding crown (with the L logo for this company) at the three position mostly buried within the bezel rather than being fully exposed. The back of the case is secured with four screws and the lugs, most notable on the back of the case are square and small. On the bezel at one end there is an ovoid aperture and one can see the black strap passing beneath the bottom of the bezel. The lugs are therefore hooded or hidden from view, except when this watch is looked at from the back. Some of these watches allow you to remove the outer gold band on the back of the case, the outer band sitting on a hinge and allows one to use that outer gold back as an easel for setting the watch up as a table clock. I am not certain if it can be done with this particular model, but I do think it can. The side with the buried crown has a hinge at both ends which allows one to open up the skeletonized gold back edge or easel and requires removing the alligator straps. This is what it would look like once you have opened the stand for the watch and removed the straps: https://en.wikipedia.org/wiki/Jean_Lassale#/media/File:Jean_Lassale_05.jpg In other words, the watch case has a folding clip, which enables the watch to be placed on a table as a little clock as well as using it as a watch. The watch is fully integrated with a Jean Lassale black alligator strap. The inside of the back cover carries the Swiss hallmark for 18 k gold, the profile of Helvetia and the .750 for 18k (18/24ths=.750) It is accompanied by a Poinçon de Maître -A hammer head with the number 122 indicating that another watch company Oreade, Manufacture de Boîtes SA has confirmed the 18k gold quality of the metal. Dial: A square silvered dial with rounded corners has applied gilt metal baton hour indices, gilt baton hands and is marked, “Jean Lassale, Geneve in the upper dial and their L within a square cut corner box in the lower dial. Usually at the very base of the dial is the word ‘Swiss’. Movement: This is a round damascened nickel movement, 1.2mm thick, the calibre 1200 made by Jean Bouchet-Lassale following the design of Pierre Mathys, master watchmaker in La Chaux-de-Fonds, who in turn used the earlier inventions of Robert Annen, who previously had the idea of using ball bearings in small scale horology. There is a large solid brushed brass ratchet wheel with the smaller spoked and fenestrated crown wheel, an index regulator jeweled to the center for making the movement faster and slower. There is gold engraving on the back plate, “calibre 1200, Jean Lassale, Geneve, and nine jewels, adjusted to five positions, Swiss and (serial number) 3666”. The key to this movement being different is based primarily in a technical trick was to mount all moving components on one side only, with the other side "flying". The barrel (with mainspring and ratchet wheel) was free-floating, guided only by three side ball bearings rather than a traditional pivot, and also held the ratchet wheel, mounted on another ball bearing. Microscopic ball bearings were used instead of pivots for most wheels. Everything was supported on a single plate with no bridges apart from the escapement pallet and balance wheel. Despite the thin profile, the movement presented at the Basel Fair operating at 28,800 beats per hour and had a 50 hour power reserve on a single winding. CONDITION: Case – good to very good condition with a moderate amount of scratches on the bezel. Dial – Good overall, but the gilt batons are not solid gold and are beginning to oxidize and turn dark in many areas. Movement – Remains in very good condition and assumed to be working. HISTORY: Jean Lassale was founded by 1974 as a brand of Bouchet-Lassale SA of Geneva. The brand name comes from the founder, Jean Bouchet-Lassale. The initial products were simple dress watches with oval, round, or square stepped gold cases and black dials. The company also produced jewelry watches and other dress models before focusing on ultra-thin. At the Basel Fair in 1976, Jean Lassale introduced the thinnest watch movement in history, the hand-winding Cal. 1200 and automatic Cal. 2000 at 1.20 mm and 2.08 mm, respectively. Designed by Pierre Mathys, it would become the company's claim to fame and their downfall, launched just as quartz movements were becoming prized. This movement caused a sensation and received much press for the young brand, however, with various models with tonneau, square, and round cases and a model with an integrated bracelet. The company produced both quartz and mechanical watches, casing a 1.2 mm mechanical movement or 1.25 mm quartz movement in a 3 mm case. These movements and patents were purchased by Claude Burkhalter, who founded Nouvelle Lemania in 1982. The resulting movements were licensed to Piaget, who has continued this tradition. Lassale had switched entirely to quartz movements in the 1980s, produced in association with Seiko, and tried to diversify from the ultra-thin market. The company was purchased by Seiko in 1979. TECHNICAL SIDE: The company Bouchet-Lassale was founded by Jean Bouchet-Lassale on October 8, 1976. Jean Bouchet-Lassale was a Swiss watch company that designed the Calibre 1200, featuring the thinnest mechanical watch movement: 1.2 mm In the 1970s, Pierre Mathys, master watchmaker in La Chaux-de-Fonds, designed and built the prototype of a revolutionary watch caliber, with the goal of making the thinnest watch in the world. To achieve this feat, Mathys based his design on the work of Robert Annen, who previously had the idea of using ball bearings in small scale horology. Mathys decided to remove the bridges and counter-pivot, and instead use ball bearings for the axis. The calibre 1200, with its automatic version the Calibre 2000, were first presented at the Foire Internationale de l’Horlogerie in Basel in April 1976. This mechanical, hand-wound movement has a diameter of 20.4 mm, and a thickness of 1.2 mm. There is an automatic version which is 2.08 mm thick. It holds 14 ball-bearings. Each one uses 0.20 mm balls. These ball-bearings are inserted in a platine which is 1.2 mm think. Its frequency is 21,600 Alt/H, and its power reserve is 35 hours. It has 11 jewels. The calibre 1200 (and its automatic version 2000) were built from 1976 to 1979 in the factory that the company Bouchet-Lassale SA had built on 30 Rue des Voisins in Geneva, Switzerland. The gold cases came from the « Ateliers réunis », a company also located in Geneva. The patent for this watch movement was applied in Switzerland on 1976, February 18. It was then applied in the USA on January 2, 1979 under the code US4132061A. The Abstract of the patent is : “An extra-thin manually or automatically wound watch movement in which at least one wheel is pivoted in an overhang position by means of a single miniaturized ball bearing.” COMPARABLES: ~https://www.barnebys.com/realized-prices/lot/jean-lassale-geneve-watch-1976-iEn1A67Bga (SOLD IN 2015 FOR $554) https://www.barnebys.com/realized-prices/lot/jean-lassale-an-18ct-gold-diamond-and-ruby-set-bracelet-watch-with-fitted-box-1980-s-4pywv28ci (This is a gold and diamond version using the calibre 1200 movement which sold back in 2008 for $2581) ~https://www.barnebys.com/realized-prices/lot/longines-jean-lassale-ultra-flat-18k-gold-watch-c7cX-LU3B5 (This is the self-winding version in gold, no diamonds fitted with the calibre 2000, the automatic version of the manually wound caliber 1200, which sold in 2016 for $2200. Both calibres 1200 and 2000 were produced from 1976 through 1979 in Geneva. ) ~https://www.liveauctioneers.com/item/64513989_jean-lassale-geneve-very-rare-18k-gold-wristwatch (using the calibre 1200 this ultrathin example in a round gold case sold for $1875 in 2018) **N.B. ~https://www.invaluable.com/auction-lot/vintage-jean-lassal-18k-gold-super-thin-wrist-wat-c-6584D3EAE7 (offered at auction in 2020 but did not reach minimum of $1500 and was passed) PRICING: Actually the movement is the real unusual item here, although the case turning into a little table clock is also extraordinary. The watch is rather small and of course thin by modern standards, but it is a little piece of horological history, a footnote at least, and is handsome to boot. It does bother me that in 2020 if failed to reach $1500. In today’s marketplace which has opened up a bit since 2020, I would place a fair market value on this watch of $1400-$1750 simply because of its rarity, and unusual movement, a little marvel in itself. I enjoyed doing this appraisal for you and learned a bit myself about watch history, which I always enjoy. Thank you for choosing mearto.com for your appraisal, and good luck with the watch. My best, David
