Stradivarius violins are regarded as highly valuable, exceptionally well-crafted violins. The most valuable violins were made by Antonio Stradivari in the 17th century. Stradivarius violins can reach up to $3.5 million at auction. Naturally, such a lucrative market has led to a rise in counterfeit violins claiming to be from the Stradivari stable. The chances of finding a Stradivarius in your attic are slim to none, but it has been known to happen.
All Stradivarius instruments have labels visible through the f-hole. If it is a relatively new piece of paper, written in plain English, then it is not a real Stradivarius. Anything which starts with "Made In___" was produced after 1957. Stradivari instruments had a printed label , written in Latin. The label reads: "Antonius Stradiuarius Cremonenfis; Faciebat Anno 17", which means "Antonius Stradivari made this in Cremona in 17". The last two numbers of the year are usually written in by hand. If they are printed, then it is more likely a copy.
If the violin has "sotto la disciplina" written on its label it was not made by Stradivari himself but under his supervision. It may still be worth a lot of money.
One of the principle reasons that Stradivarius instruments are so widely regarded is that they are said to have a unique sound that is very difficult to replicate. Players say they get the impression of controlled power, says music commentator Miles Hoffman.
Stradivarius have a greater range and resonance than other violins, and respond in a big way to minor changes by the player. There is also greater projection of the music played. The sound that the audience hears will be the same as what is heard "under the ear" by the player.
Looking at the labels, and seeing how it plays compared to a genuine Stradivarius, are good first steps to seeing if it is real or fake. Consult an appraiser if you believe it to be genuine. They will be able to look at other aspects, such as construction of the violin. Construction is important because the material used in the Stradivarius will have to conform with materials available to violin makers in Cremona, Italy in the 17th Century.