Music lovers have been celebrating since a library in north-west France stumbled upon a previously unknown score by Mozart. Scrawled on a piece of paper the size of a text book in barely legible ink, it has been described as one of the most important discoveries in decades.

The score consists of several bars of melody in D minor and signed WA Mozart. It is believed to be an piece of liturgical music which the composer never went on to complete.

It is believed Mozart wrote this score at a time when he was not obliged to write for the church (around 1787) which suggests he was doing it for his own pleasure and therefore implies he did have a genuine interest in theology and the church.

There are about 100 examples of musical scores in the hand of Mozart but most of these are for works which were completed and the melodies widely familiar. This piece which has never been performed or heard will be staying in the library but it is believed that if it were to go to auction it would be worth around £60,000