Omega De Ville Prestige Tonneau

Davidt

I’d be careful opening the back with that case pry. It doesn’t look the most delicate or precise and you can already see gouge marks between the case and caseback

ErichKeane

Looks like a 1120 powered Omega Prestige, Ref # 168.1220

https://watchcharts.com/watch_model/51639-omega-de-ville-prestige-168-1220/overview

Yours is gold it appears (but I don't know how to read gold hallmarks), which perhaps makes it a little more valuable, though the case is somewhat well worn.

As far as I can tell, everything looks right. I found a bunch of photos with that movement that have a serial number above the "Swiss Twenty", and quite a few that don't, so I dont have any other feelings on it.

Looks like it is a 1990s watch, 31mm x 42mm

I found a handful listed around $1500-$2000, though all seem to have not had any bidders/buyers/interest at that rate, so I suspect that the valuation from watchcharts isn't terribly inaccurate.

Overall, a nice watch that you should enjoy wearing, and if it is worth it to you, put the $4-500 into a good service.

dsio

These are pretty cool, this variant is Ref 4603.21 but keep in mind that it's a press-fit gold case-back in an odd shape, and even when new and correctly sealed by a watchmaker it only has 30M water resistance.

With some age and wear, I just wouldn't get it wet or even consider it splash proof anymore.

Porteroso

Being solid 18k gold, I'd imagine it has a value of around $1,000. But probably only a bit more than scrap plus part out. I'd keep and wear it! A service and gasket for sure.