UBB.threads Forums Edged Weapons SS Dagger Forum '36s Gau'd and Why?

Fred, Iron based crossguards IMHO are a late variant and are very rarely seen. In my limited experience they are always on later vintage dagger NOT M33's.
Perhaps you know better.
The SA example you show above I strongly suspect is a RZM dagger from the brightness of the fittings and the tag. Indeed these often show corrosion. This is most often caused from the acid in the wood reacting with the fittings. The other cause is intergranular corrosion from impurities,(lead content) in the zinc.
The only corrosion I've ever seen on a nickel silver crossguard is from that green stuff, (vertigis, I think it's called), sorry I can't spell.
Regardless the gau stamped crossguards we are talking about are nickel silver not iron based. I know they are fine on a chained SS. I've bought 'em from Vet's families and so have lots of others. Are they original and exactly put together that way from the factory?- IMHO Yes.
Do they sell for less than unmarked crossguards- Yes. Why? Because some have cast doubt on them and collectors are paranoid about such things. As I said earlier price is a function of the market. I do not believe that they are the result of some grand consiracy by people to put one over on collectors.
They do however repesent an opportunity for some to pick up a M36 at a bargain price.