Hello Michele,
Thank you for sending in this gold pocket watch to mearto.com for an appraisal. I shall try to help you with that today. Since I have no heard back from you I have decided to proceed with the appraisal based upon the set of photos you supplied to me.
TITLE:
Gent’s, 50mm, 18k yellow gold pendant wound, keyless, savonette pocket watch, made by the Longines Watch Company, St. Imier, Switzerland circa 1905-1910.
PROVENANCE:
“This pocket watch possibly came from Italy. My mother inherited it. It has never been exhibited.”
DESCRIPTION:
Case: 50mm in diameter this is a three leaf, 18k gold open face pocket watch currently being used as a brooch, with a fluted coin shaped gold pendant and round bow placed at the three position relative to the dial (savonette) and opposite the case hinge. The back cover is polished but not engraved while the inside of that cover reveals the 18k gold mark and the Swiss hallmark for 18k gold (the profile of Helvetia). In addition, there is a round Longines logo enclosing a winged hourglass and marked E.F. Co. (Ernest Francillon Company) and a seven-digit case number. The gold cuvette bears the name Longines and multiple medallions marked, “4 Grand Prizes- Paris, Paris, Brussels, and Milan”.
Dial: Not shown but assumed to be a while enameled dial with upright Arabic hours, open bar minute track, sunken subsidiary seconds dial @6 and the upper dial center signed Longines.
The hands were often skeletonized gilt Louis XVth style or steel spade hands.
Movement: Not shown but assumed to be a gilt split three quarter plate movement, jeweled, with bimetallic balance wheel and Swiss made regulator.
Condition: Case – Good condition with modest amount of scratches. Dial – Not seen. Movement- Not seen but considered original, genuine and functional.
HISTORY:
Longines - The original pioneers for Longines were watchmakers Jonas Raiguel (1782) and Auguste Agassiz (1832) of St. Imier, Switzerland. The Longines-Wittnauer Watch Company was an American agency founded by Auguste Agassiz circa 1847 in New York City. The first Longines Swiss factory was built by his nephew, Ernest Francillon in 1867 at St. Imier. This established a firm and lasting link between America and Switzerland for the production of watches. This was the first Longines factory that made watches by mechanical interchangeability of parts and utilized standardized machine methods. The first in-house Longines movement was created in 1867. Francillon was the first watchmaker to introduce the winding crown (All watches before that were wound with a key.) The same year Ernest Francillon returned from the World's Fair in Paris with a bronze medal for this watch. Due to prolific growth the factory buildings themselves regularly had to be adapted to the needs of a flourishing enterprise which, by 1911, employed over 1,100 people and sold its timepieces worldwide. The company’s various technical research projects earned so much acclaim abroad that Longines could claim the title of “leading prize winner” at international exhibitions up to the Barcelona Exhibition of 1929. It garnered ten Grand Prix awards (Antwerp 1885, Paris 1889, Brussels 1897, Paris 1900, Milan 1906, Bern 1914, Genoa 1914, Paris 1925, Philadelphia 1926 and Barcelona 1929). The history of the company is well known and easily researched on the internet, so I will not go into detail except for some interesting items...A letter exists from the 1885 International Inventions Exhibit in London which contains information about Longines: By 1885 they had added steam and water power to drive their machinery. They tried to prove interchangeability of watch parts by demonstrating that holding two dozen watch plates on wire strings one could see clearly through all of the jewel holes...In 1874 Longines filed for a Swiss trademark under the graphic symbol of an "hour glass with wings'. Originally these wings were more up and down than later trademarks where they are seen as side to side. The original trademark was finally registered in 1880 by the Swiss government. In 1905 their trademark of Longines written in script was registered. The word Longines in printed letters was registered in 1942 (was used before that date also). In 1957 the most famous trademark, the word Longines with the hour glass and stretched out wings was registered...For your convenience I will list some of the Longines serial numbers found on their watch movements. The serial numbers found inside the case are those of the case maker, not the watchmaker. 500000 in 1888; 1000000 in 1899; 1750000 in 1905; 2500000 in 1911; 3250000 in 1915; 4250000 in 1925; 5000000 in 1929; 5500000 in 1937 and 6000000 in 1940...
In 1874 Longines filed for a Swiss trademark under the graphic symbol of an "hour glass with wings'. Originally these wings were more up and down than the later trademarks where they are seen as more side to side. The original trademark was finally registered in 1880 by the Swiss government to Ernest Francillon. The 1880 trademark was "E.Francillon placed over the wings over the name Longines over Swiss".....The next trademark was from May 1886 and was the word "Chasseral placed over the wings floating above a mountain range with the word Longines at the bottom". This was granted to E. Francillon & Company....In May of 1889 the trademark found on your case of "EFCo over the wings over the word Longines all in a circle" was granted to Ernest Francillon & Company.
COMPARABLES:
https://www.liveauctioneers.com/item/91210191_gold-pocket-watch-longines (sold for 800 Euros in 2020)
https://www.liveauctioneers.com/item/85396675_18k-pink-gold-longines-two-color-hc-pocket-watch (sold for $1500 n 2020)
https://www.liveauctioneers.com/item/84611144_an-18k-yellow-gold-open-face-pocket-watch (sold for $950 in 2020)
https://www.liveauctioneers.com/item/80768524_longines-18k-yellow-gold-pocket-watch (sold for $950 in 2020)
https://www.liveauctioneers.com/item/80197434_gent-s-50mm-18k-yellow-gold-monogrammed-savonette (sold for $850 in 2020)
PRICING:
In today’s market place your mother’s pendant watch in 18k gold and marked clearly as being made by Longines has a fair market value in the range of $800-$1000. Retail values would be about twice that amount. I will make the extraordinary assumption that the unseen dial and the unseen movement are in good condition and original to this case, genuine and functional.
If necessary, I can always look at further photos and update the appraisal at any time in the future.
I hope you continue to enjoy this handsome pocket watch. It was my pleasure to do this appraisal and I thank you for choosing mearto.com.
My best,
David

Dear Michele,
Thank you for contacting Mearto with your appraisal inquiry. So that I may best assist you, can you please upload better images for me. The photos you have supplied are illegible. I need higher quality photos so that I can see and read everything on the case of the watch, both sides of all the covers and, of course, I need a dial to look at, and if possible the movement.
Whatever instrument you used to take these photos is not of high enough resolution that I can do an appraisal from. Please ask someone you know for help with the photos.
I look forward to hearing from you and working with you on this item.
My best,
David