I have a Gillette and Johnston master clock I would like to sell do any of my fellow members know what a fair price would be for this clock? It is complete and has the invar pendulum rod and heavy invar pendulum bob.
Does it work? I can’t give you a value because I’m not very familiar with vintage electric clocks. I will say It has a nice (although utilitarian) cabinet and a nice dial. I think electric clocks tend to have less value than their mechanical counterparts. There are early electric collectors out there though. I would think this one could easily find a place in such a collection.
The thing to consider when selling a larger clock is location. Shipping for that thing would be expensive… which limits you to someone within a three or 4 hour drive.… assuming they really really want it.
Is it running? Is there a battery pack or AC adapter that comes with it? Has it been serviced? Do you have any documentation on the clock?
I paid $100 for my Stromberg master clock which is in a seth Thomas case.. and then had it serviced by ken reindel @ kens clock clinic... i think that was $350-ish. i purchased a battery pack and controller from him for another $80 or so, but then switched to a wall-wart power supply i had lying around.
i think i paid $400 for my gents, and serviced that one myself... but there are a couple of service/maintenance guides available. the sliding resistor in the left of yours and the slave movement look very gents-like.
i have an ibm that someone put a synchronized motor in... paid about the same for that, because i liked the pendulum.
if it were mine, i would list it on craigslist and facebook marketplace at $500... or $400 if i wanted slightly more attractive bait. running, serviced, documentation would all add to perceived/actual value... but it’s only worth what someone will pay for it and you want a clock nut who’s within pickup distance... unless of course you sometimes drive down to the bay area or other parts that would expand your market with you delivering.
A G&J electric master clock is shown in Collectable Clocks (2001 reprint), it refers to the patent # 194407 which was taken out in 1921 and appears to refer to the design of the armature to eliminate noise. The case is different to this one. The valuation in the book is £850 for a mahogany case and £600 for oak, the book also shows what appears to your case with a value of £300. It should be stressed that is almost 20 years ago when prices were much higher for clocks.
Values are what someone will pay, which, as has been stated in the thread depend on location and freight costs etc. I could not suggest any value that you might realise in the USA.
I can give a little background information on the G&J clocks (and their contemporaries) which may help. In the UK there were four 'main brands' of 1 second pendulum gravity arm style master clocks which had a 30 second impulse to drive slave clocks. Although there are differences, they are broadly compatible as regards slave dials.
The most common were Gents and Synchronome, both of which were made in some quantity roughly for the period 1910 to 1980s. They change hands frequently on the major auction sites and so a 'value' can be obtained there. Generally speaking Synchronome clocks fetch slightly more as they are considered a little nicer to look at and are slightly less noisy. Both are excellent and reliable timekeepers with invar pendulum rods.
The less common are G&J and ECS (English Clock Systems, a division of Smiths Industries who made large quantities of clocks and watches).
ECS were made from roughly 1945 to circa 1960s - and though quite lot less common than Gents or Synchronome are only a little more 'desirable' as collectors items (rarity value). They can be a little less easy to set up and get running.
Finally G&J. The first clocks were introduced in the late 1920s and were usually in a rather elegant case with a slightly pedimented top similar to early (pre 1920) Synchronome clocks. The mechanism was a little different in that it had been designed such that it was quieter running than the other clocks due to the design of the solenoid having a longer but gentler movement. Early clocks had a similar solenoid arrangement for the pilot dial. These pedimented case clocks were soon superseeded by a flat top case design similar to the contemporary Synchronome and pilot dial movements changed to a more conventional design (like Synchronome). Most G&J clocks are found in this case flst top style. After WW2, the 'round corner' case identical to the contemporary Synchronome was used, but relatively few clocks were supplied in this case style probably through the 1950s into the early 1960s. This is the style of the original poster's clock. At the time - the G&J operation was under the same ownership as the Synchronome company.
Overall G& J clocks are relatively scarce - and the slightly quieter running makes them a little more attractive - and they are nice reliable clocks and keep time well. They will drive 30 second single polarity (Synchronome, Gents, or ECS) slaves as well as G&J slaves.
Unfortunately there are no serial numbers or records, so accurate history and dating is not possible. Generally in the UK G&J clocks sell at a significant premium over a similar clock made by Synchronome.