Purple Madder is a combination of Madder lake derived from the roots of the Madder plant and Spirulina Blue derived from the algae of the same name.
In conjunction they produce a cool, dark purple with a surprising amount of tint power, it will certainly 'stand up' in mixes with other colours. Also having great synergy with the other colours in this range.
It's tints when white is added are cool bluish purples and a wide range can be produced. This would be a perfect opposite to the much warmer Carmine purple.
Pigments - Spirulina & Madder Lake
Vehicle - Cold pressed linseed oil
Opacity - Semi-Opaque
Tint Power - Medium