U of S | Mailing List Archive | alt-photo-process-l | RE: [Norton AntiSpam] RE: Ferric Oxalate or Ferric Ammonium Oxalate

RE: [Norton AntiSpam] RE: Ferric Oxalate or Ferric Ammonium Oxalate



AFAIK, it may crystallize if it's a very strong solution which was kept
in low temperature. I can confidently say that the usual 40% solution
(1.07M) is quite stable in ordinary room temperature (based on my
experience with if after extensive usage in last 2-3 years). IIRC,
Mike's New Chrysotype manual says that the 1.4M solution will keep
indefinitely (uncontaminated and kept away from UV light in brown
bottle) after mixing, waiting (to let crystals form - if any) and
filtering. My 1.4M solution haven't formed crystals either after mixing
and when I checked it 1 month later...

Best regards,
Loris.

-----Original Message-----
From: EJN Photo [mailto:ejnphoto@sbcglobal.net] 
Sent: 03 Kasım 2006 Cuma 08:46
To: alt-photo-process-l@usask.ca
Subject: RE: [Norton AntiSpam] RE: Ferric Oxalate or Ferric Ammonium
Oxalate


...

I do keep some in the darkroom and use it for Chrysotypes. Since I don't
know it as well as FO, I don't want to make any claims about shelf life
that I haven't seen. I thought that Mike has cautioned about letting it
go too long however as it may form solid crystals of an insoluble form.