Russian Watch Pendant

[#1]

I recenlty bought a watch on eBay and I was wondering if someone could tell me more about it. It says Zarja, 21 Jewels, Made in USSR on the face with a stamp of Au5 on the side.

[#2]

Hi,
Zarja watches were not expensive.I bougt once 10 Zarja watches for my mum in order just to replace them one by one when it stopped.
Au5 imho does not mean gold(aurelium) ,because for gold items we have stamps 585 or smth like it.

[#3]

Au5 means the watch is gold-plated with 5 microns of gold. This is ultra, ultra thin, gold-plating. Most gold-plated watches have plating 10-20 microns thick.

Greg