Fladgate 2014 London: Is this a repeater?

[gocargo]

Hi, I've a 2 piece ornate and engraved pocketwatch from my late father's estate. It's medium size and has roman numerals on a white face and single crystal glass. The large stem is not for turning but rather for depressing (aprox 7 mm) to activate something, and when I do it sounds like it's winding a spring or spinning something inside. Once I remove the watch from the gold outer case, there is a square keyhole on the rear of the inner case, probably to wind? Then when I open up the inner case, on the backside is a small silver half-moon dial with single digit numbers and another smaller square keyhole for this mechanism. There are 3 letter & 2 ? hallmarks on the inside of the outer case. The back of the watch mechanism is where it's engraved in cursive writing: 2014 Fladgate, London and below is a half-blue spring-steel clip that appears to hold the guts in place. I've NOT opened that portion up for further investigation.

Here's the link to several photos of my watch, click on them individually to enlarge: http://s17.photobucket.com/albums/b72/gocargo/pocketwatch/

Where would I go to have this serviced, obtain operating instructions and to buy (or to have made) the winding keys?
Thank you in advance!

 

[Jerry Matthews]

Looks like you have a very fine watch there. There are two Fladgates listed in London. John was apprenticed in 1743 and died 1781. The business was carried on by his widow until 1793. The other is Thomas, and all it says about him is that he worked pre-1772. It is not difficult to slide that blue spring clip clockwise to lift off the dust cover. That will give you a much better view of the movement, and might even have the maker's first name or initial inscribed there. But whether it is John or Tom, your watch is certainly 18th century.

That spinning noise you hear when you depress the stem is probably a striking mechanism. It's purpose was when you wanted to know the time in the middle of the night you didn't have to light a candle----just depress the stem and it would strike the last number of hours.

When you remove the dust cover you will find the half moon dial you describe is actually a full circle. This is the regulator. Turn it clockwise to make the watch run faster---but personally I would be very wary about turning it.

Any good jeweller could probably get a key for you. But if you look on eBay you can probably find a set of 12 modern watch keys for about $10--$15, one of which should fit the winding and adjusting square. You also use a key for setting the hands, turning the square at the centre of the hands.

I would be very interested to see a close up of the hallmarks on the case. My guess is that this is a gilt case---not solid silver or gold---and thus it will not be properly hallmarked. But it may be gold, in which case it will be hallmarked and we can tell you when the case was made, and probably by whom.

I don't know where you can get an 18th century verge fusee serviced in the US, but someone else on here may be able to advise.

Thanks for sharing your late father's watch. It is a real beauty.

 

[Burkhard Rasch]

Hi GOCARGO
A good day and wellcome to this message board!As Jerry says You have a verry fine and rare and valuable watch:An 18th cent.(probably quarter)repeater.
Original keys are sometimes found on fleabay.These watches are usualy wound from the back,the hands are set from the front by the same key on the central square.Never turn this counterclockwise!!Service is delicate and expensive and even when exellently put in order expect a dayly error of at least 30-50 minutes.
Burkhard

 

[gocargo]

Thank you for the quick replies! I do now recognize the silver "bell" attached to the back of the inner case. I did slide the blue spring-steel and open the dust cover. Engraved on the mechanism is what appears to be in cursive Jn.Fladgate London 2014. There is a cut crystal (gem?) embedded on the back underneithe the dust cover too; it wouldn't be a diamond? Also, I'm now able to recognize the small hammers on the side.

Anyway, since I didn't have my macro camera lens with me tonight, I thought I'd post some London hallmarks I found online that are nearly identical to what's on the backside of my outer case. From my less-than amateur observation, they appear to say that this is sterling silver, although the watch case looks like gold to me. The little "b" seems to indicate that it's either 1777 or 1817, but they look similar according to the 925-1000 com site. Finally, the maker hallmark is "HPC" but I couldn't find anything about them.

I'll try to get some good closeups this weekend.

 

[Jerry Matthews]

Wow, this is pretty exciting. We now know the maker was John Fladgate. The hallmark date is 1777-78 (two years overlap because until recently London changed the date letter in May.) The case is 22 carat gold. Case maker was Hannah & Peter Crammillion of Clerkenwell Green London. I would love to see a close up of the movement---I'm sure it is a real beauty.

What Burkhardt says about these old verge fusees having an error of 30--50 minutes a day is generally true. But I do have one from 1776-77 that is accurate to a minute a day---face up on the table, of course, I don't advise carrying these old timepieces around.

He is absolutely right about not turning the hands back (counter clockwise). Normally it doesn't matter which way you turn the hands, but with a striking repeater it would be disastrous.

Look forward to some more photos

 

[gocargo]

Here's a closeup of the hallmarks as best I can do with my basic dig camera. I also loaded more closeups on my photobucket site: http://s17.photobucket.com/albums/b72/gocargo/pocketwatch/

 

[Jerry Matthews]

Great photos and a fabulous watch. Every part of it appears to be the original. The hands are especially fine. I can confirm what I said above about the hallmark date and case maker.

I hope someone on this message board on your side of the Atlantic can advise you on where to go to have a watch like this serviced, and where you can obtain a proper valuation on it.

 

[Luca]

Just wanted to say I admire your beautiful watch! Rare to see in such pristine condition. And thanks for the tons of photos.

Luca

 

[Burkhard Rasch]

Hi Gokargo!
Great pics of a great watch.Congrats!What I said about acuracy means:You cannot catch a bus with it in everyday live.I have some of these(not as beautyfull as Yours) in "running order" which means for me:They are running for 24-36 hours when left wound alone on a table with the above given acuracy of ca.30 min.This was far enough in the 18th.cent.to attend any term You had.There is no "operating instruction" for a watch like that but many good books to explain the technical detais.See to get one.In general a watch is run by winding and setting the hands,so its not that complicated exept that You must never adjust the time by setting the hands backwards in a repeating watch.That´s why I mentioned that first.Have You already found the chain yet?If You look inside the mvmt.with a magnifying glass You´ll see a fine steel-chain like on a biscycle for power tranmission.I allways admire the watchmakers of the 17-18th.cent.for making a thing like that with their means!
Regards
Burkhard

 

[gocargo]

Hello good fellows, time flies and life got in my way, so I've yet to locate a horologist here in the states to service my (above mentioned) late 1700's John Fladgate repeater pocket watch.

I performed a Google search but surprisingly there's not much additional information since my post here 14 years ago, about John Fladgate watches. Apparently this repeater pocket watch really is a seldom seen item.

 

[gmorse]

Hi gocargo, and welcome back to the forum,

I'm afraid you may have some difficulty in finding someone willing and competent to service your watch where you are. Repeaters of this period aren't actually rare, but they are uncommon and they do require specialist knowledge in servicing them. I don't advise you to run the watch at all until it's been properly serviced, especially since the repeating work sounds as though it's faulty.

There is an adjuster for the speed of striking, consisting of a screw head which alters the engagement of a pinion with the previous wheel in the strike train. It's probably this screw in the red circle on your watch, and turning it too far can result in the pivot being broken and the whole pinion falling out, resulting in the striking running so fast that you just hear a buzzing noise, as you originally described.



Your watch has what's known as a pulse piece; the small steel lever at V poking through the slot in the inner case and bezel should match up to a button in the outer case, (seemingly missing). Holding that button in whilst pushing the pendant in to activate the repeater caused the hammers to be held away from the bell so that the striking was just felt. Handy during a long sermon or in the theatre when you needed to know the time without being seen to look at your watch!



I don't think anyone so far has identified the maker of the cases, which were Hannah and Peter Cramillion in Clerkenwell Green, London. The case is apparently silver gilt; the lion passant signifies sterling silver and the date letter is as has been said, for 1777/8.

I'm afraid the close-ups in your photobucket account are no longer accessible, which is why we always encourage people to post images here on the forum rather than on a third-party site. If you still have them, it would be very helpful to see them here.

The timekeeping abilities of verges are widely underestimated. When in good condition and properly restored, (which most aren't I'm afraid), they're capable of plus or minus one or two minutes a day.

Good luck in your search for a restorer.

Regards,

Graham

 

[gocargo]

I received a horologist's name whom has expertise with repeaters here in the states and I've sent him an email about a service and possible repairs.

I will update once I learn more and/or receive back from him. Thank you

 

[Incroyable]

Hi gocargo, and welcome back to the forum,

I'm afraid you may have some difficulty in finding someone willing and competent to service your watch where you are. Repeaters of this period aren't actually rare, but they are uncommon and they do require specialist knowledge in servicing them. I don't advise you to run the watch at all until it's been properly serviced, especially since the repeating work sounds as though it's faulty.

There is an adjuster for the speed of striking, consisting of a screw head which alters the engagement of a pinion with the previous wheel in the strike train. It's probably this screw in the red circle on your watch, and turning it too far can result in the pivot being broken and the whole pinion falling out, resulting in the striking running so fast that you just hear a buzzing noise, as you originally described.

View attachment 717847 View attachment 717848

Your watch has what's known as a pulse piece; the small steel lever at V poking through the slot in the inner case and bezel should match up to a button in the outer case, (seemingly missing). Holding that button in whilst pushing the pendant in to activate the repeater caused the hammers to be held away from the bell so that the striking was just felt. Handy during a long sermon or in the theatre when you needed to know the time without being seen to look at your watch!

View attachment 717849

I don't think anyone so far has identified the maker of the cases, which were Hannah and Peter Cramillion in Clerkenwell Green, London. The case is apparently silver gilt; the lion passant signifies sterling silver and the date letter is as has been said, for 1777/8.

I'm afraid the close-ups in your photobucket account are no longer accessible, which is why we always encourage people to post images here on the forum rather than on a third-party site. If you still have them, it would be very helpful to see them here.

The timekeeping abilities of verges are widely underestimated. When in good condition and properly restored, (which most aren't I'm afraid), they're capable of plus or minus one or two minutes a day.

Good luck in your search for a restorer.

Regards,

Graham

Yes I once owned a late 18th century silver verge fusee--a rather ordinary one--that only gained about two minutes a day.

 

[Rich Newman]

Lovely watch.

The timekeeping abilities of verges are widely underestimated. When in good condition and properly restored, (which most aren't I'm afraid), they're capable of plus or minus one or two minutes a day.

I'm so glad gmorse corrected the fallacy, often repeated, that watches from the 18th century kept time to a half-hour a day or worse. Watches shortly after the invention of the balance spring in 1675 were expected to keep good time and did. The few who could afford a pocket watch also had house clocks and knew very well what accurate time for the day was and a minute or two per day was probably the worst case when new.

 

[dshumans]

I completed repairs on this excellent watch and it is keeping time within 6 minutes per day. I received some really great help from Graham Morse on the Forum here about the all-or-nothing piece action in this type of repeater and this type in general. Thanks for the wonderful help Graham! There is a video at the end of this work report showing half-quarter repeating. Also worth noting is that the time mechanism is not connected to the repeater mechanism until you depress the pendant to activate the repeater, so you can set the time forwards or backwards at will. I have repaired hundreds of repeaters and all but a very few were designed to be set both forwards and backwards. As with all complicated watches, always set the time slowly and with minimal finger pressure in case of a fault in any mechanism, and if you feel resistance, don't try harder.
Doug Shuman

 

[gmorse]

Hi Doug,

Regarding the gold case, the UK 18 carat standard wasn't reinstated until 1798, so this case will almost certainly be 22 carat.

Great writeup and the video is well worth watching. It also shows how small these watches are, especially considering how much mechanism is contained between the plates! I do love the sound of these early pieces with the bell instead of gongs, a really sweet sound.

Regards,

Graham

 

[gmorse]

Hi Doug,

To expand a little on Stogden; opinions vary on when he lived, and even how his name was spelt, but he was probably working in the first and second quarters of the 18th century. His design is unique in the way it functions, it's believed that it was based in part on a Tompion design, but it was used by Graham, Mudge, Dutton, Ellicott and Vulliamy amongst others. The Vulliamys in particular continued to use the design when most other makers had abandoned it for the more modern designs. Most examples are like this one in that they strike half-quarters, and I think it's a tribute to your expertise that you deciphered its working even though you'd never seen one before.

Looking again at the top plate, the aperture for the balance staff is small and circular, which would not be the case if it had started life as a verge; it would have been larger, with one side squared off to accommodate the escape wheel. George Graham developed the cylinder escapement and after perfecting it in the mid-1720s, he never again made a verge watch.

Regards,

Graham

 

[dshumans]

Hi Doug,

To expand a little on Stogden; opinions vary on when he lived, and even how his name was spelt, but he was probably working in the first and second quarters of the 18th century. His design is unique in the way it functions, it's believed that it was based in part on a Tompion design, but it was used by Graham, Mudge, Dutton, Ellicott and Vulliamy amongst others. The Vulliamys in particular continued to use the design when most other makers had abandoned it for the more modern designs. Most examples are like this one in that they strike half-quarters, and I think it's a tribute to your expertise that you deciphered its working even though you'd never seen one before.

Looking again at the top plate, the aperture for the balance staff is small and circular, which would not be the case if it had started life as a verge; it would have been larger, with one side squared off to accommodate the escape wheel. George Graham developed the cylinder escapement and after perfecting it in the mid-1720s, he never again made a verge watch.

Regards,

Graham

More great information Graham. Many thanks. I have worked on a number of 18th century repeaters but with different repeating works like this half-quarter repeater from prior to 1850:

Hi Doug,

To expand a little on Stogden; opinions vary on when he lived, and even how his name was spelt, but he was probably working in the first and second quarters of the 18th century. His design is unique in the way it functions, it's believed that it was based in part on a Tompion design, but it was used by Graham, Mudge, Dutton, Ellicott and Vulliamy amongst others. The Vulliamys in particular continued to use the design when most other makers had abandoned it for the more modern designs. Most examples are like this one in that they strike half-quarters, and I think it's a tribute to your expertise that you deciphered its working even though you'd never seen one before.

Looking again at the top plate, the aperture for the balance staff is small and circular, which would not be the case if it had started life as a verge; it would have been larger, with one side squared off to accommodate the escape wheel. George Graham developed the cylinder escapement and after perfecting it in the mid-1720s, he never again made a verge watch.

Regards,

Graham

Graham,
Thanks much for more insights. I had worked on a number of 18th century repeaters, like this mid-1700s German half-quarter repeater

and this later 18th century half-quarter French:

So working on a Stogden with your help was most enjoyable. I will add that the cylinder escapement is original. Do you have insights into early porcelain dials, or could it be original?
Regards,
Doug

 

[gmorse]

Hi Doug,

Well, these dials aren't actually porcelain, they're a vitreous enamel (glass) on copper or, in the better quality pieces, gold substrates. This Fladgate one isn't original, at this date it would have looked much more like this 1762 example, with beetle and poker hands:



As the 18th century progressed, the Arabic 5-minute numerals gradually grew smaller, until by the 1790s they were more often missing altogether, and the hour numerals were changing from Roman to Arabic. George Graham is credited with popularising these one-piece enamel dials at around the time he introduced his cylinder escapement.

The quality of the engraving on the balance cock is good, and doesn't compare at all badly with this Mudge & Dutton cylinder:


All in all, it's a good example of the puzzles that earlier repairers and their works can pose to restorers today.

Regards,

Graham

 

[dshumans]

Hi Doug,

Well, these dials aren't actually porcelain, they're a vitreous enamel (glass) on copper or, in the better quality pieces, gold substrates. This Fladgate one isn't original, at this date it would have looked much more like this 1762 example, with beetle and poker hands:

View attachment 723574

As the 18th century progressed, the Arabic 5-minute numerals gradually grew smaller, until by the 1790s they were more often missing altogether, and the hour numerals were changing from Roman to Arabic. George Graham is credited with popularising these one-piece enamel dials at around the time he introduced his cylinder escapement.

The quality of the engraving on the balance cock is good, and doesn't compare at all badly with this Mudge & Dutton cylinder:

View attachment 723575
All in all, it's a good example of the puzzles that earlier repairers and their works can pose to restorers today.

Regards,

Graham

Graham,
As I have another observation, this thread just keeps going. I now have run it a lot more and have noticed that it runs a little slow when fully wound, runs about 6 min/day fast in the middle of the fusee and runs much faster (+55 min/day) towards the end of the fusee. While I normally don't like to wind a 250 year old watche all the way up, I did once to time it. I presume that originally the mainspring characteristics were matched to the fusee and that this is a replacement mainspring which winds with more strength at the start than the original. When wound up 3/4 of the way, it runs 12 hours gaining only 3 minutes.
Doug

 

[gmorse]

Hi Doug,

I now have run it a lot more and have noticed that it runs a little slow when fully wound, runs about 6 sec/day fast in the middle of the fusee and runs much faster (+55 sec/day) towards the end of the fusee. While I normally don't like to wind a 250 year old watche all the way up, I did once to time it.

Although cylinders are frictional rest escapements, unlike verges they aren't so dependent on the mainspring power curve for their rate. The geometry means that more power from the mainspring at full wind is partially compensated for by the increased friction it generates between the escape teeth and the cylinder walls. What you're seeing may well be due to your observation about a mismatch between fusee profile and mainspring, but it could also be linked to the state of the escape teeth. Like most English cylinders it probably has a brass escape, whose tooth tips can become blunt with all those years of wear, and that can have an effect on the friction. I'd be inclined to try altering the mainspring setup a little in both directions and see what effect that has on the regularity of its rate. I wouldn't recommend re-profiling the escape teeth to any extent since that results in increased drops.

You're lucky that the tangent screw for the mainspring setup is still there, making one of those is a pain.

I also notice that the cylinder shows little or no sign of wear, which probably indicates that it's a replacement, and both pivots appear to be flattened, which won't help in horizontal positions. That lower pivot seems very chunky as well. It's very likely to be running in a plain brass hole in the potence.

Regards,

Graham

 

[gmorse]

Hi Doug,

I can fully understand your reluctance to dismantle a full-plate repeater, but I find the judicious use of rubber bands is a great help in guiding the dozen or so arbors into place on reassembly.



Regards,

Graham

 

[Incroyable]

Hi Doug,

Well, these dials aren't actually porcelain, they're a vitreous enamel (glass) on copper or, in the better quality pieces, gold substrates. This Fladgate one isn't original, at this date it would have looked much more like this 1762 example, with beetle and poker hands:

View attachment 723574

As the 18th century progressed, the Arabic 5-minute numerals gradually grew smaller, until by the 1790s they were more often missing altogether, and the hour numerals were changing from Roman to Arabic. George Graham is credited with popularising these one-piece enamel dials at around the time he introduced his cylinder escapement.

The quality of the engraving on the balance cock is good, and doesn't compare at all badly with this Mudge & Dutton cylinder:

View attachment 723575
All in all, it's a good example of the puzzles that earlier repairers and their works can pose to restorers today.

Regards,

Graham

When were the champleve dials in fashion?

 

[bruce linde]

I completed repairs on this excellent watch and it is keeping time within 6 minutes per day. I received some really great help from Graham Morse on the Forum here about the all-or-nothing piece action in this type of repeater and this type in general. Thanks for the wonderful help Graham! There is a video at the end of this work report showing half-quarter repeating. Also worth noting is that the time mechanism is not connected to the repeater mechanism until you depress the pendant to activate the repeater, so you can set the time forwards or backwards at will. I have repaired hundreds of repeaters and all but a very few were designed to be set both forwards and backwards. As with all complicated watches, always set the time slowly and with minimal finger pressure in case of a fault in any mechanism, and if you feel resistance, don't try harder.
Doug Shuman

great job, great watch!

 

[gmorse]

Hi Incroyable,

When were the champleve dials in fashion?

Although one-piece enamel dials were being made before the 1720s when George Graham began to popularise them, they were fairly rare, and before that, champlevé dials had been the usual dial style stretching back into the 16th century and possibly earlier.They did continue to be fitted later into the 18th century but were increasingly unusual. The design of the enamel dials was generally simpler than the elaborate champlevé styles, and by the time enamel dials were becoming common, the way the time was presented had largely settled down into what we now regard as the standard, the 'sun and moon', 'wandering hour' and 'six-hour' styles amongst others being discarded.

Regards,

Graham

 

[John Matthews]

Doug
An excellent description of the watch and the steps taken to restore. Did you record the number of teeth on the escape 13 or 15? Were there any initials stamped on the underside of the cap?

Graham - I have a record of Fladgate cylinder (#1647 movement only), that has the original Graham style steel cylinder and banking pin. Do you think this would be that type of original cylinder, rather than a ruby cylinder?

#1647 has the similar dial to the one in your post #19, with slightly smaller Arabic numbers and without the slot bisecting 30.

John

 

[gmorse]

Hi John,

I have a record of Fladgate cylinder (#1647 movement only), that has the original Graham style steel cylinder and banking pin. Do you think this would be that type of original cylinder, rather than a ruby cylinder?
#1647 has the similar dial to the one in your post #19, with slightly smaller Arabic numbers and without the slot bisecting 30.

It's hard to tell whether it ever had the Graham type banking, but the edge of the balance cock table hasn't been cut back in a later repair to accommodate a radial pin in the balance rim, there's no sign of one on the balance, and since Doug didn't find it necessary to split the plates, we don't know whether there's a peg in the potence. It certainly isn't visible from the view of the top plate. Cylinders will work without any banking, although it isn't a safe practice.

I'm not sure when ruby cylinders were first used in English cylinders, but I suspect that this would always have had a steel cylinder.

You'll have noticed that the slot in the dial in post #19 is truly radial rather than canted, because the watch has a separate spring for the case bolt. The Arabic minute numerals did become progressively smaller over the course of the century.

Regards,

Graham

 

[John Matthews]

Graham

I read a little more and according to Clutton & Daniels, the combination of steel cylinder and brass escape was favoured by Graham & Mudge. Arnold and Ellicott sometimes used a ruby cylinder and a steel escape. Made me wonder whether if a brass escape is present, than that would favour a steel cylinder. Have you even encountered a ruby cylinder with a brass escape.

John

 

[gmorse]

Hi John,

Have you even encountered a ruby cylinder with a brass escape.

Yes, I've handled a movement with one, signed for James Muckarsie London, subsequently mounted as a small clock. It dates from around 1790.



Regards,

Graham

 

[gocargo]

Update. Honorable mentions to Ethan Lipsig for the referral and Doug Shuman for repairing this John Fladgate, London repeating pocket watch.. Thank you very much !

Doug says it's 18k solid gold pair-casing and a half-quarter bell repeater.

I inherited this watch from my Father's estate after his passing about 25-yrs ago and I'm unsure whether it's a family heirloom. Unfortunately my Pop never mentioned this pocket watch to me during his lifetime.

Here's a YouTube link that Doug sent me of the pocket watch in action.

 

[gmorse]

Hi gocargo,

As it was probably made before 1798, it will be 22 carat gold as that was the only legal standard up to that date.

Heirloom or not, it's a fine watch and a fortunate survival, and I think it's now going to become an heirloom!

Regards,

Graham

 

[Dr. Jon]

As Graham, wrote before the case is 22K gold. That was the standard until 1798.

18K gold was stamped with an "18". The photos in Doug's very lovely report show the marks on the outer case. The include a lion "rampant" which was used for silver, gilt silver, and 22K gold until a separate mark for 22K gold was introduced much later.

So, unless your cse is gilt silver, it is 22K gold, as Graham was written

 

[John Matthews]

It is probably worth recording the history of hallmarking of gold ...

• 1300 Act (Edward I) 19.2K
• 1477 Act (Edward IV) 18K
• 1576 Act (Elizabeth I) 22K London (Leopard's Head & Lion Passant) - the same as silver
• 1680~ regulated Chester marks begin
• 1729 Irish Act confirmed 22K (Harp Crowned). Introduced the Hibernia (duty paid) mark
• 1738 Act (George II) - confirmed the 1576 Act
• 1784 King's Head (duty paid). In Ireland 20K (Plume of 3 Feathers) & 18K (Unicorn's Head)
• 1798 (George III) watch cases exempted from the payment of duty
• 1798 Act (George III) 18K - (Crown & 18) - first time gold marks distinguished from silver.
• 1824 Act (George IV) Birmingham empowered to assay gold.
• 1844 Act (Victoria) 22k (Crown & 22)
• 1854 Act (Victoria) 15K (15 & .625) 12K (12 & .5) & 9K (9 & .375) - note no Crown
• 1903 Sheffield empowered to assay gold (York Rose) - Crown is the Sheffield town mark

This is my understanding. It was in 1784 that Dublin led the way in hallmarking gold differently silver with the introduction of the Plume of 3 Feathers for 20K and the Unicorn's Head for 18K. Not until 1798 was the Crown & 18 first used in London & Chester and not until 1844 that 22K was required to be stamped with Crown & 22.

So given these marks on this case...



for London 1777/78, these are valid for silver, silver gilt and 22K gold. Testing would be necessary to confirm which and this would apply for all similar mark up to 1843/44

John

 

[gmorse]

Hi John,

Doug has mentioned that the cases tested for 18 carat, but I don't know what method he used. If it was one of the small test kits, I doubt if they're configured for 22 carat. Other examples I've seen of this type of pierced and engraved repeater case have been solid gold.

Regards,

Graham

 

[John Matthews]

Graham

I am not familiar with the 'off the shelf' test kits, nor the technology they deploy. Therefore, I do not know whether these kits are able to differentiate between a thin surface coating of gold and solid gold. I have seen comments that imply that they cannot. Today, gold plated silver can have a gold fineness down to 9K and must not exceed 2 microns thick, although I believe the term vermeil is used if the thickness is over 2.5 microns. In the C18th the fineness would be higher and I suspect thicker, especially on better quality items. I am not suggesting that the Fladgate repeater case is not gold, but I would like to understand how reliable these 'small testing kits' are in distinguishing well preserved C18th gilt from solid gold objects'

John

 

[Incroyable]

The most surefire way to test gold content would be one of those precious metal analyzer guns but only a well stocked jeweler would have those since they're quite an investment. I think a used one costs in the low 5 figures.

Those guns can test the fineness down to the precise percentage of alloys used.

 

[Dr. Jon]

I believe that Doug's test was good enough to distinguish gilt silver from gold.
If it was an acid and touchstone test it shows that the gold was at least 18K. That and the hallmark are very good indication that the case is mostly 22K gold. I write mostly because I know of instances where English hallmarked cases have come up short.

The other common test method is conductivity. It costs more because of the consumables and in my experience it reads a bit high but it measure through some depth and it will identify gold plated over silver.

i

 

[gmorse]

Hi John,

Therefore, I do not know whether these kits are able to differentiate between a thin surface coating of gold and solid gold. I have seen comments that imply that they cannot.

If they work by rubbing a part of the case on a touchstone and then seeing how various acid solutions react with the mark, then I don't see how they can differentiate.

Regards,

Graham

 

[dshumans]

I believe that Doug's test was good enough to distinguish gilt silver from gold.
If it was an acid and touchstone test it shows that the gold was at least 18K. That and the hallmark are very good indication that the case is mostly 22K gold. I write mostly because I know of instances where English hallmarked cases have come up short.

The other common test method is conductivity. It costs more because of the consumables and in my experience it reads a bit high but it measure through some depth and it will identify gold plated over silver.

i

I tested outer and inner cases with acid and touchstone. I always use a sharp edge of the case where it will not show and press reasonably hard against the stone to get an inch long strip. This ensures that if it is gilt, or similar that the underlying metal is in the test stripe. This method only distinguishes between 10K, 14K and 18K, because my kit has no test acid for 22K. As I put in the report, I believe it is 22K from 1777/78
Doug