Prussian Blue is a deep blue colour. It was made by German chemist Diesbach around 1704 making it the first synthetic blue pigment. It quickly gained favour as an alternative to genuine Ultramarine.
Intense Blue (Phthalo Blue) is a deep intense blue which when undiluted, forms an inky blue-black. It is made from the modern pigment Phthalocyanine which was introduced in the 1930s.
Cobalt Blue Hue is a clean blue pigment closely resembling Cobalt Blue. Genuine Cobalt was discovered in 1802 by French chemist Thénard as an alternative pigment to the expensive Lapis Lazuli blue.
