The Aldis scopes I've had; all four of them, LOL, had excellent glass, with the exception of that abomination of a sporter scope they made up from left over bits after WWII, or as it before??

That said, it seems that some exchanges of glass for certain strategic materials the Germans required did indeed take place during WWI, so without testing I can't say where the fine glass in those Aldis scopes may have come from.

Can glass be precisely and non-destructively analyzed for chemical composition?