Hi Mark,

Thanks for your fast response.

: It's the black PVD with the coating removed Mick, potentially with
: a pewter refinish, though the case for the black ones is
: roughened like this to allow the finish to "take".

I was not aware of this rough pre-finish.

However, I still assume some kind of coating as the scratches (not only the worn edges) are shiny:

This (only) looks like Titanium.

Anyway, I will leave this cool matte surface like it is.

: The clasp doesn't look like the
: one supplied with the jubilee bracelets on the barrels, might
: not be contemporary with the watch.

Although the clasp feels lightweight and cheap, it perfectly matches the case.

Cheers,

Mick