Cotman Water Colours are a range of water colours that are made to our normal high quality standards but costs are kept to an economical level by replacing some of the more costly pigments with less expensive alternatives.The range consists of 40 colours in tubes and pans which possess good transparency, excellent tinting strength and good working properties. The range offers a balanced spectrum of 40 colours which are available in Half Pans, 8ml tubes and 21ml tubes. To see the colours available in each size.There are also a number of excellent water colour sets available in the Cotman range.PigmentsCosts are kept to an economical level by replacing some of the more costly pigments with less expensive alternatives. Pigments derive from a number of sources: Some are natural products, notably the earths, eg. umbers, ochres; others come from metal compounds and are sometimes termed 'traditional' or 'genuine', eg. ultramarine.The distillation of petroleum yields an ever widening range of organic pigments which are often termed as 'modern'. Many of the pigments used in Cotman are organic.