Series number: 1 Chemical description: Complex sodium alumino-silicate containing sulphur Colour index name: PB29 Colour index number: 77007 Permanence rating: A(iii) ASTM lightfastness rating: I Transparency/Opacity: T

French Ultramarine is a rich transparent blue.

As with all Winsor & Newton colours, every colour in the range is individually formulated to take advantage of the natural characteristics of each pigment and to ensure the stability of the colour. The vehicle (oil modified alkyd resin) allows the colour to dry quicker whilst retaining the other characteristics of conventional oil colour.

Because alkyd resin has physical properties that differ slightly from those of traditional oils, the pigment load is somewhat different as well. Experienced painters will notice slightly greater transparency compared to Artists' Oil Colour. The colour has been formulated to offer the greatest degree of tinting strength possible (consistent with good handling properties), and to take full advantage of the true characteristics of each pigment.