According to a BBC report, a piece of rare Mozart sheet music was almost accidently put up for auction at Oxfam in Newbury, Berkshire.
Ester Lee, a classical musician and volunteer at the auction, first noticed the value of the piece by the engravings. She translated the French on the cover and discovered it was a collection of Sonatas for piano and violin. But more than that, her research lead her to find that this piece is actually a second printing of a first edition and the only one of its kind to still exist.