I have an unusual case on an Illinois KWKS (at least it is unusual to me). The case is an unremarkable Silveroid except that both front and back bezels attach like a bayonet mount lens to an SLR camera. The images below show the watch movement and inside back cover respectively. I ommitted the dust cover which snaps on. The inside rear cover is labled Silveroid, some barely readable numbers below and something unintelligible above. I am wondering when this case was produced and as it seems to work so effectively, why I haven't seen more of them.

Ron Birchall

Here is the inside back cover:

A very interesting case that I have not seen before. The logo identifies it as a product of the Keystone Watch Case Co. The uppermost stamp looks like it begins with "PAT ..." and is probably a patent date. With that in mind can you make any more sense of it?

Is this a keywind case or is it a stemwind case converted for a keywind movement?

Good eyes Jerry, The upper inscription does look like "PAT" and what follows looks more like "APP". What follows is 4 characters which are a total blur. Could be "lied" or a year. In either case, not much help.

I was hoping someone might recognize this case.

Ron

The case is definitly for key winders. There are no slots for levers and no provision for a stem or crown. Sorry I didn't get a photo of the whole case.

Ron

It probably says "PAT.APPL.FOR" or something of that meaning. I wonder if the patent was ever granted? It looks like an attempt at a dustproof keywind case. The unusual half-twist back and bezel would be much easier to manage on a keywind watch than than a threaded back and bezel, but more dustproof than the usual hinged b&b. If you have a chance, a picture showing the entire case would be appreciated.

Terry

Here is the full front with the back bezel.

Ron

Ron;
The alloy that is silveroid has been around for a long time. The earliest watch case application that I have seen is 1883, but its actual use may date from the late 1870s. It seems that most watch case manufacturers had their own tradename for the same substance. Silveroid was used by Keystone and Silverode was used by the Philadelphia Watch Case Co.

And the back with dust cover installed. Both dust cover and bezels fit snuggly but are still easy to remove and replace. It seems to be a very nice design. I wonder what happened.

Ron

Keystone Watch Case Co's Patent for the Silveroid trademark was filed on Oct 17, 1900 however it is also listed as being in use since Jan. 1, 1886 Claims: Watches, Cases and Movements.


Although the Trademark under the Silveroid name had also been Filed Oct. 17, 1900 and in use since Jan. 1, 1886

the Trademark with the
"Co" inside was Issued March 23, 1905

As Jerry mentioned, "Patent Applied" for is correct. It was often used on items that had patents in process, or that already existed.

Proof of when the item had first appeared with this trademark by the Company.

On patents there is an Application date, and a Registered Date.

According to an Illinois database, my watch was made or at least started in 1886 which makes it reasonable that the case and watch belong together. As there are no visible case screw marks, I think I will conclude that the two are a matched pair.

Thanks to all for the response.

Ron

I still wonder though, why this case was not more prevalent.

Ronald,
It's quite a nice case, I like the look, and being Silveroid it will last forever.

It looks like yours may have been one of the first ones they made, since the patent application date is the same as yours.