G in Diamond Logo , Whom represents it ?

[Mustafa Umut Sarac]

My friend is looking for the identification his wide angle symmetrical lens engraved with G in diamond logo.

Do you know that maker and lens ?

Thank you,

Mustafa Umut Sarac
Istanbul

[Steven Tribe]

Age?
Black or brass?

[BradS]

Diamond-G.....almonds? or, kitchen matches?

[polyglot]

Might help if you had a photo of the logo... And then you could do a google reverse-image search on it.