Lamp Black Watercolour by Cotman
Colour number/code: 337 Series number: 1 Chemical description: Carbon black, Carbon black Colour index name: PBk7, PBk6 Colour index number: 77266, 77266 Permanence rating: AA ASTM lightfastness rating: I Transparency/Opacity: O Granulating/Staining: -
The range of 40 colours are chosen according to mass tone (colour from tube), undertone (bias of colour when in a thin film), colour strength, relative opacity and the character of the pigment itself. The resultant colour spectrum ensures the largest number of colours can be mixed.