I didn't know it was a rarity : ) I picked it up years ago at Photo Eye in Santa Fe when I lived in Taos and made regular trips to The PLatinum Gallery delivering work.
Originally Posted by donbga
Your materials will not change much over the time of making Ferric Oxalate. The only change will be to the H2O2 over time as it loses some of its strength. How much time is does it take? It is not a process that takes alot of time of active participation but periods of letting it sit. There are two steps that require a little real time; 1) measuring the chemicals, 2) achieving a finished solution. If you make good notes, like you were taught in basic chemistry, your solution will pretty be the same batch to batch. It may not be the same as BA&SA, Formulary or Artcraft but that does not make it bad, but rather it makes it your solution. What makes it bad is ferrous ions running around. How do you stop that from happening? keep extra oxalic acid in solution.
What are you going to use it for? the requirements for ferric can be slightly different for different processes. If you can make your own ferric oxalate, and your own potassium oxalate, you free yourself up from a supply chain. You gain more control over your process and have more money to spend on silver, platinum and palladium or gold.
For an investment of $180.00 you can make 2.5 liters of liquid ferric oxalate. I can forward to you a method of making it or you can go to the site that Sandy posted for Jeffrey and download how to make powdered.
Many years ago I got in a discussion with Dick Sullivan about his ferric powder on the Alt photo list. I had used B&S ferric since 1983 after Tom Millea stopped making a liquid for us. I have known Dick for a long time.
Experiments were being done by my ex business partner John Rudiak and David Michel Kennedy to try and improve BA&S powder or at least make it in line with the conversation.
AS part of making ferric oxalate, one converts ferrous to ferric. If you can do this during the process of making it, you can surely do it to stuff you already have. You can't stave off the process for ever though. Sandy was going to try and freeze some. He may be getting ready to thaw it?
Life is as consistent as you make it. Ferric oxalate is easy and cheap to make. And while as Mike Ware describes it as ill defined, it still works and has worked for a long time.
Concentration of your liquid can be best estimated by specific gravity. In Stevens book there is a neat chart that the University of Notre Dame Science department whipped up for him. Is it definitive? Well no, but short of anything else it is a bench mark that I have used for 12+ years and it hasn't failed me.
In the life time of print making, what are a few hours? if you have the lab ware and can get the H2O2, I can sell you a small amount of AFS- Ammonium Ferrous Sulfate and if needed Oxalic acid, and you can then see for yourself. The best judge of how something will work for you, is YOU.