This is the only one in the envelope that says "...in Gold on demand..." the others are old 2$ normal bills and a few very, very worn wrinkled 1$ silver certificates.
Part of this tread was to un-confuse me as the only bills I had ever seen were the gold backs (because those have value above face). "All the ones I have found" from my post above was just my google image research, searching this forum etc not actual beautiful bills.
My personal life addiction is coins so I doubt I'll add any gold back gold certificates. :)