This is all I have, is it possible to tell from just this picture if this is real? If real, what would it be worth?
Looks like a threaded collar at the bottom, that being the case it's real.
Wow!! How can you see that? But anyway, is that the way to spot the fakes of these. The real ones are threaded molded right into the glass??
Yes, all originals have the threaded base with a copper collar/flange that screws on. If it has a glass molded flange to fit into the globe holder on a pump then it is a reproduction. I attached a photo of a Texaco globe to show the threaded collar.
Unless it is a 7" Flange then it's the Earlier ones w/ raised letters [RED CROWN ETHYL, RED CROWN & SOLITE]. Beware of RED CROWN Raised letter w/ 6" Flange Base, REPOP.