The world's smallest painting of Mozart, a miniature he gave to his cousin and lover, has sold at auction for the first time.

Mozart gave the portrait to his lover, and recieved one in return

The painting came directly from the descendants of Maria Anna Thekla Mozart, otherwise known to Mozart as Basle (little cousin). It made £218,500 ($342,619) as the highlight of Sotheby's Music, Continental and Russian Books and Manuscripts sale in London on November 20.

Made in 1777, the portrait is just 4cm tall and was likely intended for the locket of his first love and cousin, who gave him a portrait of her in return.

"One of only two authentic paintings of Mozart remaining in private hands and one of only a dozen or so authentic paintings and drawings of the composer, this object's significance is virtually unparalleled," said Dr Stephen Roe, Sotheby's worldwide head of books and manuscripts.

"What is particularly exciting is that the portrait has never been reproduced in colour in the standard Mozart literature, and it is only now that the miniature's special qualities can be more widely appreciated.

"The artist, though unknown, has caught the essence of the composer."

Mozart's relationship with his cousin began when he visited his uncle in Augsburg in 1777. The pair held a long correspondence until 1781, when Mozart became infatuated with German soprano Aloysia Weber, before being rejected and turning his affections to her sister, Constanz.

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