The Liber colorum secundum magistrum Bernardum ('Book of Colours according to master Bernard') is a medieval treatise on miniature painting and book illumination.
Written in a Medieval Latin interspersed with several expressions in the Italian Lombard dialect it stems from 13th century Northern Italy.
The eponymous magister Bernardus (or 'master Bernard') was most likely a cleric working in a scriptorium to whom later collections also attribute further artisanal instructions not related to book painting.
These treat: The Liber colorum was first published, based on three manuscripts, with a translation into Italian and a commentary by the Milanese conservationist Paola Travaglio in 2008, followed by a 2016 re-edition after the discovery of a fourth textual witness.
In 2023 Travaglio and Thomas Reiser published a German version with an expanded commentary.