Longines Cal.431 Ultra-Chron Automatic 18ct 1971 37mm Tonneau


Fully Inspected, Serviced & Guaranteed

A Beautifully Well Cared For & Lightly Used Example

A Stunning Retro-Modern Dial with Onyx Inlaid Hour Indices

Oversize Yellow Gold Tonneau Case, 37.5mm Excluding the Longines Crown

Supremely Accurate, Cal.431 Ultra-Chron Hi-Beat Automatic Movement

Original, Unrestored and Untouched Dial, in Simply Superb Condition

New Tan Leather Strap and Longines Gold Plated Buckle

All in Absolutely Top Grade & Simply Stunning Condition

Vintage Longines Presentation Box Included

VGWL Lifetime Authenticity Guarantee

VGWL 12 Months’ Written Warranty*

Free Worldwide FedEx Delivery

Free UK Special Delivery

VGW Reference: L991
Price £3,600


Add to favourites heartRemove from favourites heartADD TO FAVOURITES
DO YOU HAVE A WATCH LIKE THIS TO SELL?Add to favourites heart


Longines is one of the very oldest Swiss watch manufacturers with an unparalleled history of invention, innovation, patents and awards. The company is also responsible for some of the most beautiful watches ever made, however, it has been treated as something of a Cinderella among the watch collecting fraternity until relatively recently. Longines is now rightfully returning towards the elevated status it held during the pre and post 2nd World War period when it ranked among the very best of Swiss watch manufacturers. Within the past five years, Longines vintage watches have risen again to the admiration and popularity they deserve, with values rising by around 10 – 20% per year. On certain models, such as the now legendary Longines Calibre.13ZN chronograph, prices have simply sky-rocketed!

Why this watch is Important

Regular visitors to this site will know that even though VGW specialises in watches which are in the main, over 50 years old, we pay a great deal of attention to the accuracy of each of the watches we list here and offer for sale. So much so, we do our best to ensure each watch is calibrated to keep time to within 10 secs per day following its restoration and include our final test figure in each listing. We then guarantee all of our watches will remain accurate to within 30 secs in 24hrs while under our 12 months’ warranty unless otherwise stated. This, along with our Lifetime Authenticity Guarantee are just two of our ‘points of difference’, which as far as we know, no other comparable vintage watch dealer offers.

Of course, some watches are designed to be more accurate than others, and when Longines released its new Calibre 431 Ultra-Chron in 1967,  it was advertised as “The most accurate watch in the world” and was guaranteed to keep time to within 1 minute per month, or 2 secs per day! Longines timed the release date of this watch nicely, to coincide with the 100 year anniversary of the founding of the company in 1867.

The Longines Cal.431 movement broke a lot of new ground when it was released as it was one of the first to operate at 36,000 beats per hour. These ’10-beat’ movements ran twice as fast as typical movements of the period, which was the principal advantage in gaining more accuracy over their competition.


Hi-Beat watches are designed for greater accuracy, as all other things remaining equal, the faster the escapement or heartbeat of a watch, the greater its accuracy. Very simply, this is because time is divided into smaller fractions of a second in faster running movements. Zenith, Girard-Perregaux and Longines were the first of the Swiss manufacturers to bring hi-beat watches to the mass market, with Girard-Perregaux releasing the very first in 1965 with its HF automatic – an example of which we listed and sold recently. Hi-Beat movements beat at 36,000 beats per hour, which is twice as fast as a standard watch movement. These are also known as 10-Beat movements because they beat at 10 beats per second. This is very fast, even today, as only very few premium watches run at this speed. This is because, not only do they need very precise design and manufacturing techniques, but they require a great deal more power and special lubricants to function properly. If we were to use vintage cars as an analogy, hi-beat movements are the Formula 1 movements of their day!

The Case

The Ultra-Chron range was a great success for Longines and many different models were produced throughout its 9 years of production. These included many sports and even dive watches. Longines overcame the technical challenges well, but, one could suggest, quite uncharacteristically, it lost its way a little aesthetically, along with one or two others during the 1970s, particularly so with its Ultra-Chron range. The company knew, of course, it had to face a totally new challenge which was a serious threat to its life. The advent of quartz watches and the revolution which followed saw all but the very strongest Swiss watch brands taken over, or out of business. The Ultra-Chron was conceived, designed and marketed to meet this challenge and demonstrate just how accurate a mechanical watch could be. To differentiate and emphasise the technical advance this watch represented, almost each and every model was given a ’70s ‘futuristic’ look. This meant some quite brash and even outlandish styles which we struggle to have any affection for, even though they carry ‘the world’s most accurate automatic movement’ of the time. 

There are one or two Ultra-Chron watches which still retain the looks and feel of a traditional Longines gold dress watch. This tonneau example in 18ct yellow gold, is a nice example, in truly outstanding condition. The multiple curves and lines of the case design are simply sublime. Almost organic, face to face it is a work of art, in the same way a beautiful car can be. This is a two-piece design, but from every angle on the wrist, it looks like it was hewn from a single solid piece. 

At 37.5mm across, excluding the Longines signed crown, and 38mm top to bottom, this is the largest Ultra-Chron we have ever seen. It is even larger when one considers the diagonal dimension is 44mm!

The case-back carries the Ultra-Chron motif which is crisp and unworn. On the inside, all is as expected and signed ‘Longines’, ‘Swiss Made’ with the Longines brand, Geneva Swiss 18ct hallmarks and the Longines model number 8430-1. The case has been carefully inspected and it is faultless with no dings, scratches or other signs of wear visible to the naked eye. The case-back is of full thickness and has never been engraved.

As ever, our standard advice applies: Vintage watches should be kept clean and dry at all times.

The Dial

As discussed above, the style of this watch is futuristic, without being over the top or outlandish, as with some other Ultra-Chron designs which can be a little brash. The dial here is silver-white, which looks a little warmer under indoor lighting as we have tried to demonstrate in the photographs.

Onyx inlaid hour indices are matched with corresponding onyx inlaid ‘Index’ hands.  The dial is signed ‘Longines’ and ‘Automatic’ and carries the applied gilt Longines brand.

An applied Ultra-Chron brand and signature are found in the lower half of the dial, along with ‘Swiss Made’ at the very bottom. The dial also carries a date window between 4 and 5, which is the more natural and logical position to put this.

This is the original, unrestored dial, which is untouched and as can be seen, is in outstanding condition.

The Movement

The Longines Ultra-Chron Cal.431, Hi-Beat movement lives in that most rarified atmosphere of some of the highest performing watches ever made. For Longines to release this watch in 1967, bill it as the world’s most accurate watch, and guarantee it to be accurate to within a minute a month was an extraordinary claim for a series produced mechanical wristwatch. The challenges are significant, even today, to design and build such a watch. For example, a great deal of power has to be stored and transferred by the mainspring. This in turn, puts increased strain on the drive train of the movement. In addition, the faster-moving component parts cannot be lubricated in the normal way, simply because the oils are quickly dispersed by the faster moving parts. The teeth, in particular, are subject to increased wear and friction, reducing performance. Longines mitigated this problem by coating the escape wheel teeth with a new dry lubricant named ‘molybdenum bi-sulphide’.  

As can be seen, it is without any doubt that the Longines Calibre 431 movement and other hi-beat movements of this era represented the very pinnacle of horological achievement in terms of design, engineering and accuracy. Huge resources, investment and R&D were brought into play by Longines to produce these movements. Likewise by Girard-Perregaux to produce its HF automatic and Zenith’s Hi-Beat, which of course led in 1969 to its amazingly advanced and groundbreaking Zenith El-Primero, 10-beat, automatic chronograph. It is interesting to contemplate that without the looming challenge of electronic / quartz watches, these amazing hi-beat movements might never have left the drawing board.

The movement, as can be seen in the photographs, is as clean, bright and sparkling as you will ever see and has been expertly serviced by our vintage Longines specialist watchmaker. This involves fully dismantling the watch, three-stage ultrasonic cleaning, careful examination under high magnification of all the critical components and surfaces, replacement where necessary only with genuine Longines parts, then careful reassembly, calibration and final testing. Following restoration and immediately prior to listing, this movement was showing one of the best performances we have yet seen, even for a Longines Ultra-Chron – at zero error rate, and completely flat on our electronic timegrapher, only occasionally slipping into +1s/day and equally occasionally into -1s/day. This is as good as we have seen on a mechanical watch! We therefore have no hesitation in offering this watch with our 12 months’ warranty* 

The movement is signed ‘Longines Watch Co Swiss’ ‘Adjusted to 4 positions and temperature’ and carries the movement serial number 50,723,543 which dates this watch to 1971.

*Please note – our 12 months’ warranty is only applicable provided the list price is paid. 

The Strap and Buckle

The strap fitted is a new high quality tan leather strap with a Longines gold plated buckle. If a different colour or style of strap is preferred, please let us know and we will do our best to oblige free of charge. We carry tan, conker, dark brown and black in stock and in plain padded leather, or crocodile skin or lizard skin.

The Box and Papers

Although there are no original papers with this watch, the numbers and markings on the watch are all correct, dating the watch to 1971.

Detailed particulars will be included with our purchase receipt for your interest and security. A separate insurance valuation for the replacement value of this watch will be provided at the time of sale along with our unique ‘Lifetime Authenticity Guarantee’ which states: “If this watch proves to be anything less than 100% genuine, authentic and original, a full refund will be given at any time”.

The matching vintage Longines presentation box is included in the sale.

In Conclusion

A very special and absolutely stunning Hi-Beat automatic vintage watch from one of the most collectable, highly regarded and time-honoured vintage watch brands. This is a very rare watch due to its 37.5mm size and 18ct yellow gold case. This watch will therefore make an excellent financial investment as well as be something to use, treasure and enjoy! It is completely practical for use as an everyday watch and as long as it is well looked after and serviced every 2-3 years, it will last another lifetime. It carries a great deal more style, individuality and panache than a new watch and to buy the same quality today, would cost at least three or four times the price here.

However, you may wish to view this, as each year goes by and the world market for fine vintage gold watches grows even larger, the limited supply and high demand means prices will inevitably climb even higher!

A word on our prices – We always try our hardest to acquire the very highest quality watches we can find, before then restoring them to the highest possible standards. We then offer these at the fairest prices we can, taking into account our pre and post sales care and service. This approach means we will never be the cheapest, but nor will we be the most expensive. Indeed there are some well-known stores in West London which are highly successful charging between two to three times the price you see here. We therefore consider our prices to be good value and very fair, given the quality of watches we have to offer.

We are happy to accept payment via PayPal as this is the quickest method of payment. However, if you would like to pay by UK cheque or by bank transfer, we will be pleased to assist you with this and pass on a 3% saving to you.

Please check the import duties and any taxes your government may apply, these are different for each country and unfortunately out of our control.

We understand there may be some ‘loopholes’ that may help you avoid these charges, however attempting to use these could impact our ongoing ability to serve our growing international customer base.

For those that happen to visit the UK on occasion we are of course more than happy to store your watch until we can meet you in our offices in Kensington, London, and your watch directly to you there.

If you have any questions please call on Landline 0207 727 7095 or Mobile 07515 949250 or if calling from overseas on Landline +44 207 727 7095 or Mobile +44 7515 949250.

Please note, we also welcome part exchanges.

Please take a look at our other vintage gold watches.

Thank you.