Diffusion Transfer Reversal (DTR) uses noble metals and has a permanence greater than most silver based photographs. It is incorrect to say that instant photography is not archival. One only needs to look at the now 60 year old monochrome DTR examples at the George Eastman House to see many perfectly preserved examples. And on the subject of GEH - it is apparent to me that instant photography and its technology is under-represented. DTR is the most important (commercially, socially) advancement made in 20th Century photography and is the basis for the nanotech revolution, and other important industrial advances. To lump it all in the toy category represents a prejudice that disregards the reality of history.