The Cyanotype Recipe I use:

Solution A 
65 g ferric ammonium citrate in distilled water to make 250ml total.

Solution B 
23 g potassium ferricyanide in distilled water to make 250ml total.

Store solutions separately in brown glass bottles, away from light. 

Filter before use, and mix in equal proportions A to B

After coating dry papers in the dark or in very subdued light.  Expose until the colour changes to a dark prussian blue (this will vary dependent on the strength of your light source).

Rinse in tap water, or for a boost give your print a white vinegar rinse then finish rinsing in tap water.  The colours will continue to deepen over the next 24 hours.







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