Hi Chris

Well my question is this,, high quality pigments are used in both processes, carbon and gum, differences in application, but I cannot see any reason why one process would be considered more archival than the other, unless of course if the pigments used in ultrastable are more stable. This is a question I would think worth researching, as there is a lot of research and workers in gum who would say their prints are ever so much archival as Carbon Prints.

Kind of like the who has the bigger one, and I am thinking both processes are as stable as each other , but I certainly do not have this answer and enquiring minds need to know.

thanks Bob