Sometimes it is good to get back in touch with art materials. Not only pigments, but their interactions, behavior in dry or saturated conditions, and interactions with other substances. Today, the ‘other substance’ is salt.
I used indanthrone blue and lemon yellow to wash the watercolor paper. I spread a bit of large-grained salt (that I saved from those freezer pretzels that you microwave yourself), sprayed some clean water on it and let it dry.
I got some beautiful designs that look like crystals. I used English yellow, Sennelier red and phthalo blue to accentuate the patterns.