Stimulant Blue
Cyan, cobalt, cerulean, light intense blue.
Environmental effect
Cool, fresh, spirited, bracing, airy, blithe, elating, buoyant, invirgorating, zestful.
Traditional usage
Sky symbol; blue frit of the Egyptian sky goddess Nut; cerulean, symbol of the Heavens (Thylesius 16c). Volatile spirit colours of many petrol signs.

Power Blue
Ultramarine, royal blue, reddish blue.
Environmentalal effect
Imposing, superphysical, virbrant, pulsating and electric!
Traditional usage
Sapphire blue: sign of those who set their affections on things above (Marbodus 12c). Lapis lazuli and azure: token of truth loyalty and the highest aspiration (Occolti 16c). Colour of many nurses uniforms.

Moderate Blue
Deep turquoise, peacoak blue, sea blue.
Environmental effect
Dignified in the lighter registers, clean and aqueous: in the darker, sombre and humid. Used as a background enhances flesh colours.
Traditional usage
Symbol of pride (Occolti 16c.) as from the gladed mirror-pool of Narcissus. The Aquarian colour in astrology. The Humid pole (Albers). Colour of many hair dressings and rinses.

Subdued Blue
Chinese blue, twilight blue, dark dusky blue.
Environmental effect
Calm. Reduces pulse, repiration, metabolic and glandular activity. Is also anabolic and recuperative. Increased darkness adds a heavy and melancholic note.
Traditional usage
Cosmic symbolism: 'Blue may be seen participating in itself so much, and a step from this world, inwardly turned, that it has characterised ethereal things' (Thylesius 16c); 'an intensity of negation' (Goethe).