The sound of the Stradivari and Guarneri violins, which no one can repeat for more than 200 years, is explained not only by the art of the craftsmen, but also by the chemicals used to process the instruments. This discovery was made by biochemists from the University of Texas and National Taiwan University, who published their results in the journal Angewandte Chemie, according to phys.org.
As it turned out, in the manufacture of tools, great craftsmen subjected wood to aggressive chemical treatment - they used borax, zinc, copper, alum, lime water. These substances were found not only on the surface of the wood from which the tools are made, but also inside it. The chemicals were supposed to protect them from being eaten by worms: violins and cellos in those days often suffered from parasitized wood. Borax was used as a preservative in the manufacture of mummies by the ancient Egyptians, and then it became a popular insecticide. Perhaps, in the process of making, the craftsmen came to the understanding that the salts that they used for impregnation gave the wood special strength and excellent acoustics.
The varnish recipes used to cover the finished instrument were no secret, because the varnish itself is not a factor in determining the quality of the tone. But the process of treating spruce boards with various water-based chemicals is crucial for the sound of a bowed instrument, therefore each master had his own know-how, and they were kept in strict secrecy: this gave a serious competitive advantage. In those days, there were no patents, and it was impossible to guess how exactly the wood was processed by visual inspection of the finished product.
Antonio Stradivari (1644-1737) made about 1200 violins in his life. His clients were exceptionally wealthy people, including members of royal families. About 600 Stradivari violins have survived to this day, their cost reaches $ 10 million. Stradivari's contemporary Guarneri, nicknamed del Gesu (1698-1744), was not as popular during his lifetime, but today his instruments are considered equal in quality and are not inferior in price to Stradivari violins.