Sotheby's will offer the finest Stradivarius viola in existence, known as the Macdonald, with a world record estimate of $45m+.
The Spring sale marks the first time the viola has appeared at auction in 50 years, and is a historic moment for collectors of stringed instruments.
One of only 10 surviving violas by the great luthier, and one of only two in private hands, the Macdonald will be sold in a sealed bid process this spring in association with specialist auction house Ingles & Hayday.
The auction record for a Stradivarius instrument is held by the Lady Blunt violin, which made £9.8m ($15.9m) in 2011.
Antonio Stradivari (1644-1737) is renowned as the finest maker of stringed instruments ever to have lived. In a career that spanned 71 years, his high level of craftsmanship saw only 600 violins and 60 cellos made, with just 10 violas known to have survived.
"The finest of all Stradivari violas is generally agreed to be the 'Macdonald' of 1719. It is immaculately preserved," said Tim Ingles, director of Ingles & Hayday.
"No Stradivari viola has been on the market for the last fifty years so this is truly a once-in-a-lifetime opportunity."
Created in 1719, the Macdonald is crafted from alpine spruce on the front and a single piece of maple for the back. Remarkably, it is in superb condition, retaining the original varnish applied by Stradivari himself.
"Every field is defined by one outstanding masterpiece which casts its shadow not only on its own domain but far beyond," commented Sotheby's vice chairman David Redden.
"The instruments of Stradivari are in a class of their own among the pinnacles of human craftsmanship and the 'Macdonald' Viola stands at the unquestioned summit."
The Macdonald derives its name from previous owner Godfrey Bosville, 3rd Baron Macdonald, who bought it in the 1820s. It was last seen at a 1964 auction, where it was bought for the celebrated Peter Schidlof of the Amadeus Quartet.
One of its early owners was Luigi Tarisio (d.1854), the first real collector and dealer of fine Italian stringed instruments, whose collection was bought for £2,000 on his death without its new owner having seen any of its contents.
It was then discovered to contain 24 Stradivaris, along with 120 instruments by the top Italian masters.
The ultimate goal for a Stradivari collector is to assemble a quartet of his instruments (two violins, a viola and one cello). With the task almost impossible to achieve today, the appearance of the viola is a historic event and no doubt the world's top collectors will be prepared to make huge bids to secure the Macdonald as their own.
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