RE: slightly OT: tea toning cyanotypes

Quoting "Taylor, Jane" <taylor74@marshall.edu>:

> I assume tea is archival, but haven't researched it.

There are two aspects to tea "toning". Part of the process
results in staining of the paper. Being a simple stain
I doubt this would be archival. With cyano there is also a reaction
which forms a ferric - tannate compound . As best as I could discover
this is related to some of the "permanent" inks. I would thus think
it is good permanence, but have not managed to find any reference which
specifically comments on tea toned cyanotype. As for tea toning
silver gelatine prints, I don't know if there is any reaction with the silver.

Richard

-- 
Richard Urmonas