M48 Description: Patek Philippe Time Trials Extra grade 20J pocket watch movement only, made for Tiffany & Co, New York, 17-size, 44.0 mm front plate diameter, open-face model, Patek Philippe 1889 patent +. 1016 special stem-wind pendant-set with first instance of split-stem facilitating case removal as specified in the patent, without dial (would be snap-on canister variety white enamel single-sunk with block Tiffany signature), fully capped lever escapement with bracketed-spar Guillaume prototype balance, diamond endstones on balance pivots, 20 jewels, fausses-côtes pattern nickel damascene, s#10020 with serial number repeated on front plate next to balance, a requirement of the Geneva Observatory for submission for chronometer classification, Time Trials or competition.
Twenty numbers before this example, S#100000 was acquired by a friend of mine, with full Patek Philippe signature, identical Extra grade and balance system with Extract from the Archives. Both watches are interesting in that typical interpolation of Patek Philippe production numbers would place manufacture at 1893-4, while typical introduction of the Guillaume balance is recognized closer to 1900, even though Charles Edouard Guillaume had discovered the Invar alloy well before his patent in 1896.
He was able to design a balance that eliminated middle temperature error, characterized by the bracketed spar and more pronounced overhang, as well as bimetallic compound balance incorporating his alloy. He was awarded the Nobel Prize in 1920 for Invar, and created another horological revolution with Elinvar for use in hairsprings. The Extra grade was initially produced in 20-jewel, and later with greater jewel count, but only those watches considered eligible for chronometer classification were marked with the second serial number for Observatory submission. These are among the most recognized simple timekeepers of Patek Philippe production. Examined by yours truly, a specialist in antique and vintage watches since 1971: Good running order but in need of full overhaul, excellent movement condition overall, mild plate cloudiness.
Some microfine scratches, hardly any oxide; dial absent, needing canister type that will exactly snap over 44.0mm plate; elegant blued Louis XV hands might be original, but are atypical. Please note the order of grading terms - Pristine - Mint - Excellent - Fine - Fair - Poor. All Descriptions Guaranteed, 14-Day Return Privilege.
The item "Rare Patek Philippe Time Trials Extra grade 20J pocket watch movement only -m48" is in sale since Friday, February 23, 2018. This item is in the category "Jewelry & Watches\Watches, Parts & Accessories\Parts, Tools & Guides\Parts\Movements". The seller is "watchperson" and is located in Milford, New Hampshire. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Israel, Mexico, New Zealand, Singapore, Norway, Saudi arabia, Ukraine, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Colombia, Panama, Jamaica.