A rare third quarto edition of William Shakespeare's play Hamlet is expected to fetch up to $2 million (£1.1m) when it is auctioned in New York next month.
William Shakespeare probably wrote Hamlet in 1600-1601
The quarto - the earliest obtainable copy of Hamlet remaining in private hands - will be sold at Christie's New York auction house on April 14.
The quarto was unveiled in London on Monday by Royal Shakespeare Company artistic director Michael Boyd.
The complete collection includes 10 other Shakespeare quartos.
The quarto is part of a collection of early English drama from the estate of Mary, Viscountess Eccles - one of the foremost collectors of her generation
Other highlights include copies of Hamlet that belonged to actors Henry Irving and Alec Guinness.
Discussing the artefact with Christie's manuscript expert Francis Wahlgren, Mr Boyd described the third quarto - the final edition published during Shakespeare's lifetime - as the "gold standard" of Shakespearean texts.
His new production of Hamlet, starring Toby Stephens, opens in July at Stratford-upon-Avon.