I recently purchased an extremely thin 18k gold open faced watch that has no maker signature or marks. The watch is quite large, about 16 size. Do you know who made it? Here is a picture of the movement.

To show you how thin this is, here is a side-by-side shot of the watch next to a much thicker (but still quite thin) Elgin C.H. Hulburd.

Here is the dial.

And the back

And the serial number

I went to the GLAR today, and bought this watch, mainly because it is beautiful, but partly because it has an identical anonymous movement, identical hands, and an identical dial, except that it has a sub seconds dial. The very knowledgeable seller didn't know the maker.

Here is the back of the watch

Here is the movement

Here is the serial number, which is the same as the other watch's but plus 605.

Ethan

The mark by the serial number on your second movement is the "Geneva Seal" . This is only used on movements made in Geneva which meet a strict series of criteria.

Are there any marks or letters inside the backs of the cases ?

Dave

I am tempted to say Audemars Piaget

I see no real clues on the the inside of the back cover of either watch. Both are marked with the watch's serial number. The first of these two watches is also marked 18k and has the Swiss hallmark for 18k gold. The second of these two watches does not have gold indication, or any other hallmarkings. It looks like the rim is 18k yellow gold and the center is white gold or platinum. Besides the serial number, the only other mark is the number 52 on the next line.

Audemars made watches as thin, but the only really thin Audemars in my collection looks rather different, although the winding bridge, wheels, and click work look very similar, albeit one is layed out in reverse of the other. Here is what my Audemars movement looks like.