Antonio Stradivari. Source: What We Hear in Music, Anne S. Faulkner, Victor Talking Machine Co., 1913.

A team led by Jean-Philippe Echard from the Laboratoire de recherche et restauration in the Musée de la Musique in Paris (an institution rarely found to contribute to Angewandte papers) recently published a study where investigations performed on 5 instruments that span 30 years of Stradivari’s career, are reported. They used complimentary analytical techniques to investigate the different varnish layers. To make the long story short, they found … nothing unusual or unexpected, but only materials broadly used in this time. The varnish is essentially made of two layers, the first (lower) one being used primarily to seal the wood and made of classical siccative oil. The second (upper) layer was found to caontain the same oil mixed with organic resins, and pigment particles. The latter were identified, and again, were found to belong to broadly used materials: inorganic salts (iron oxides, mercury sulfide) or organic crimson pigments.

Spanish Stradivarius II of c. 1687, on exhibit at Palacio Real de Madrid. Author H. Svensson

In conclusion, no trace of long hypothesized gums, amber or protein was found in any of the five instruments that have been investigated. Only common materials were used, and one must admit that the extraordinary quality of his instruments was (and still is) due to Stradivari’s exceptional talent as an intrument builder, but not to supernatural trick he may have used!

Reference: J.-P.Echard, L. Bertrand, A. von Bohlen, A.-S. Le Hô, C. Paris, L. Bellot-Gurlet, B. Soulier, A. Lattuati-Derieux, S. Thao, L. Robinet, B. Lavédrine, S. Vaiedelich, Angew. Chem., Int. Ed. published online. DOI: 10.1002/anie.200905131