Potassium Thiocyanate

Potassium Thyocyanate

Posted by Pat Willard on 17th Jul 2025

I needed to make some GP-1 toner. The paper that I used to make the prints is no longer made. I had a couple boxes left that still worked perfectly fine. The paper has a bit of warmth to it, and I wanted to see how it looked a bit colder.

In my darkroom I already had a bottle of Gold Chloride 1% Solution. Using potassium thiocyanate was needed to make GP-1.

Note: The instructions indicate toning with GP-1 for 10 minutes. However, I have a 5000K (daylight) bulb in my darkroom that I use when toning prints. It allows me to tone by inspection. In this situation, the toning took about 5 minutes.