Schmincke Horadam Aquarell Paint, 5ml Tube, Chromium Yellow Deep Hue contains superior quality natural ingredients that are carefully selected in each formula for highest optimization. These quality ingredients ensure a harmonious color assortment that can easily be picked up by the brush. An optimal amount of Ox gall enables the artist to decide (and not the paint) as to where the paint should flow moist or stay dry on the paper. This semi-transparent hue is an alternative to the original toxic chromium yellow deep. There are 140 colors in the Horadam Aquarell line.