It is not in the new Complete Guide to Watches.
The case does not appear to be heavy enough to be solid gold, but I could be wrong.
Thanks

Edward

I am curious too, I have a case with the same mark but I have never been able to find anything on.

Tom

That mark has been used by two makers however there are actually 3 of those marks.

2 are Philadelphia W C Co.

Yours is the Philadelphia Watch Case Co. filed May 8, 1905.

The other Philadelphia case mark looks almost the same, and was filed Jan. 6, 1902. Used since 7-1-1889

The other company that Claims a similar trademark is Zubragg, Theophilus., Riverside, NJ Filed April 22, 1896 used since 6-1-1889

It's also listed in with the Keystone Watch Case Co.

Sheila,
Wow, that was fast, thanks a bunch! Is it gold plated? Where did you find the info?

Here is mine, it is on a size 6 hunter case, looks gold but I doubt it, still very nice.

Tom

If I'm not mistaken, they are gold filled.

They are all listed in the "United States Horological Trademark Index" by Kurtis Meyers

and

The Keystone match is from the Trademark book by Roy Ehrhardt.

Believe this mark indicates the case is made of brass. See pp 67 of Roy Ehrhardt's Trade Marks.
R/S B J

I will try to get a picture of the marks so you can see which one you think is yours.

the differences are really small, but they are different.

Bobby, Your right, I was looking for that too, and missed it. I have one and mine is brass.

I have read that some claim that theirs is Gold Filled, but have not talked to anyone else that says it's GF, only the Brass ones.
Thank you Bobby, I didn't see the marking.

Last, we did talk about this some time ago on here, and most agreed that it must be all Brass, but no one else came back with a confirmed GF.

??????