A 14th Century Jewish religious book, preserved by experts from the University of Manchester's John Rylands Library, is to go on show in New York.
Conservator Steve Mooney spent eight months working on the Rylands Haggadah, a text used by Jews on the first nights of Passover.
The book illustrates stories from the Torah and will go on display at the Metropolitan Museum of Art.
Mr Mooney said it was "a bit nerve-wracking" working on the restoration.
To maintain the high level of concentration needed, he could only work on the manuscript for a few hours a day, viewing the damaged areas under a microscope.
He said: "This has been a fascinating job and there was a real sense of achievement when I'd finished.
"But it was a bit nerve-wracking, one slip of the hand and you could remove a fragment of gold leaf or pigment by mistake."
He added: "My job is to take it to the museum by hand into a secure area where it will acclimatise before going on display. I shall inspect it to make sure the conditions are exactly right."
The Haggadah, which was produced in Catalonia, was sold by the 25th Earl of Crawford to Enriqueta Rylands, the founder of the John Rylands Library, in 1901.
The full-page miniatures in the book depict episodes from Exodus onward, starting with the call to Moses and ending with the crossing of the Red Sea.
Rylands collections and research support manager John Hodgson said: "This manuscript is one of the finest Haggadot in the world.
"It is important for its intrinsic beauty and for various textual details, but it is also a key source for the study of the illumination of Hebrew manuscripts in general."