The Catalogue Raisonné of Cândido Portinari, published in 2004, is the product of the inventory of the work of this artist, carried out as part of the Portinari Project. The Portinari Project is coordinated by the painter's only son, João Candido Portinari. The Catalogue is the first of its kind to be published in Latin America and it became an example and encouraged the development of similar projects about other Brazilian and Latin American artists. The reading of the work of Portinari, as presented by the Catalogue Raisonné, is focused on historical aspects, formal and stylistic documentation. It does not have a detailed study of the materials and techniques used by the artist. This work aims to contribute to the knowledge of Portinari's work, in terms of its stylistic influences, his painting materials and techniques. Through the methods of art technological source research and scientific analysis of 15 works of the artist, especially the mural paints Guerra e Paz (War and Peace), the present work complements substantially the extensive work already published in the Catalogue Raisonné of Candido Portinari.