Antonio Stradivari, an Italian luthier from Cremona, produced some of the world's most famous violins, cellos, and violas between the late 17th and early 18th centuries. Out of the roughly 1,100 instruments he produced, only about 650 survive today. These 'Strads' are prized for their unique tonal quality and power, often selling for millions of dollars at auction. Scientists have spent decades trying to determine why they sound so superior. Theories range from the specific chemical treatment of the wood (using minerals like borax and zinc), the density of the wood due to a 'Little Ice Age' that occurred in Europe during the growth of the trees, and the secret formula of the varnish used. Despite modern technology and carbon fiber alternatives, many professional violinists still consider the Stradivarius the pinnacle of instrument craftsmanship.