Winsor & Newton Designers' Gouache is created by combining pigment and Gum Arabic the binder that holds the pigment and gives it a creamy, flowing consistency that glides across grounds, resulting in a flat, non-streaky finish. One of the natural attributes of Gum Arabic is that it is quick-drying, allowing quick working techniques and preliminary sketching to be done. This quick-drying feature also allows work to be completed quickly, resulting in easier transporting of finished artwork.All Winsor & Newton Designers' Gouache colors are fully compatible with Winsor & Newton Artists' Colors and Cotman Watercolors. Although Designers' Gouache colors are more opaque than Artists' Watercolors, the degree to which they cover varies.Designers' Gouache may also be mixed with Winsor & Newton Artists' Acrylics and Galeria Flow Formula Acrylics. Care should be taken, however, as some gouache colors may react adversely with acrylics. Combinations should be tested on the palette paper prior to use in a painting.For design and illustration, where work is intended for electronic scanning and reproduction, illustration board or a hot press watercolor paper is recommended for use, for a flat finish that reproduces well. For fine art painting, watercolor papers are recommended.Individual tubes of Winsor & Newton Designers' Gouache are 14 ml (0.47 oz). Black and White colors are also available in larger size 37 ml (1.25 oz) tubes. Gold and Silver are available in both 14 ml (0.47 oz) tubes and 30 ml (1 oz) jars. However the formulations differ slightly. The jar formulations are metal based, whereas the tube formulations use mica based pigments that have a metallic sheen but contain no metal. The jar colors are a little more fluid and generally stronger and more opaque. The tube colors will not tarnish.95 Individual Colours available. Colours displayed onscreen on our website are representative only and the actual colour may differ slightly.