Watercolor prepared with Blue Verditer inorganic mineral pigment, chemically basic copper carbonate. This is an historical pigment, which was mostly prepared during the 16th and 17th century as a replacement of its natural equivalent, i.e. the mineral azzurite, which was very expensive, but also the most important blue pigment during the Middle Ages and the Reinassance. It's a bright light blue color, tending to green, with important granulation, low tinting strength, extremely transparent and lightfast. Incompatible with sulfur based pigments, because it would tend to blacken if in contact with them: please avoid mixing it with Ultramarine colors and Cadmium Reds and Yellows.
Colouring agent: Basic copper carbonate