Red pigment (PR 102.77015) of mineral origin obtained from kaoliniferous clays containing iron sesquioxide.
However, it has been rarely used since the Middle Ages in fresco techniques. Conversely, it found widespread use, mixed with collection, for the preparation of surfaces in gouache gilding, according to methods already widely described by Cennino Cennini (end of the 14th century).
Bolo rosso is suitable for tempera, watercolour, acrylics.