Global “cooling” seems to be one reason that Stradivarius violins have a unique sound. A mini-Ice Age that started in the middle of the 17th century caused a new pattern of tree growth. Trees grew more slowly, growth rings were narrower, and wood became denser, which could account for the difference in the sound of violins made during the 1600s and 1700s. Then again, maybe other theories explain the sound of a Stradivarius violin–perhaps 300 years of aging or a unique treatment for the wood creates the special sound. Whatever the reason, the “Strad” is still the most admired violin ever made.

There are many copies of the famous Stradivarius instruments. This violin was made by Ernst Heinrich Roth in 1924 and is marked “REPRODUCTION OF ANTONIUS STRADIVARIUS, CREMONA 1745.” It sold for $3,220 in 2005, far less than the value of a genuine “Strad.”