Daniel Smith Extra Fine watercolours are of the absolute highest quality and among the finest paints available. These watercolours are handmade in Seattle, USA, and Daniel Smith has become one of the most popular watercolour brands in the world in only a few years. These exquisite paints are more pigmented and finely ground than most watercolours available on the market. The results are vivid, clear colours with unique properties. The pigments are carefully selected and the broad, beautiful colour assortment includes historic shades, fantastic earth tones, and some of the lightest and boldest colours around. Daniel Smith aims to meet artists’ demands for lightfastness, permanence, vibrancy and clarity. And they have succeeded through continuous research and development. –Interference Blue (4001) is one of the luminous colours – special colours with optical effects found in nature. Interference colours refract light when mixed with other colours. Excellent lightfastness (100+ years), non-granulating and transparent. Tube 15 ml (corresponds with 7 half-pans). Price each.