Product Description Stonegrounds pearlescent watercolours are ideal for adding special effects to traditional watercolour paintings, for hand-lettering or calligraphy applications, and for illustration work. Try using our pearlescent watercolours on black paper for added drama. Pearlescent watercolours are perfect for adding shimmer and shine to any project, and are permanent, lightfast, and non-toxic. Midnight Blue is a dark blue hue. Transparency : Semi-Transparent Staining : Semi-Staining Granularity: Semi-Granular Pigment Number : P N/A Toxicity : Non Toxic