I do believe that one of the sets my Dad had were marked "Craftsman Vanadium"
I don't know anything other than that, except that they dated from at least the early 70s if not before.
I cannot recall a time when I didn't see them in his tools, and I'm 50 now.
I have a page about Craftsman but I could never get an exact date or era of when those were made. All I can say is that Craftsman started out (1927 or so) using Craftsman Vanadium on sockets and tools and later dropped the Vanadium.