Bob's Cyanotype formula (not mine really-just the one I use).
Solution A:
Ferric Ammonium Citrate 68 gm.
Oxalic Acid 1.3 gm.
Water to make 250 cc.
Solution B:
Potassium Ferricyanide 23 gm.
Oxalic Acid 1.3 gm.
Ammonium Dichromate 0.5 gm.
Water to make 250 cc.
Mix equal parts of A and B just before use.
Store in brown bottles. Use distilled water.
Hope this is of some use.
Bob Schramm
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