A rare 17th-century map of the world found stuffed up a chimney has been saved following intricate conservation work.

The antique produced by Dutch engraver Gerald Valck was found in 2007 during the renovation of a house in Aberdeen.

It was destined for the skip before someone had second thoughts and gifted it to the National Library of Scotland.

It is understood there are only two other known copies of the 2.2m-by-1.6m map in existence and the conservation department had to clean and restore the map, which proved to be "one of the most complex" projects the team has undertaken.

The deteriorated map arrived at the library rolled up in a plastic bag and at the time looked like a "bundle of rags" and had to be handled carefully as fragments fell off like confetti every time it was moved, according to conservation experts.

Greenock Telegraph:

The restoration project involved a variety of specialist treatments including separating the map into its original eight sections, dry cleaning and washing the paper, and re-assembling the cleaned sections onto a new paper lining.

The final stage of cleaning involved suspending the map sections individually in water in a heated sink at 40C for 40 minutes with the water being gently agitated to clean dirt from the surface. On removal they were placed in blotters to remove any excess water.

In total, the map restoration took 150 hours to complete over a period from April to September.

Clare Thomson, book and paper conservator at the library, said: "Once the map was unfurled I was able to assess its condition, which I must admit filled me with dread.

"Much of the paper had been lost and the remainder was hard and brittle in places and soft and thin in others.

"We needed to stabilise it to prevent any further deterioration, make it robust and easier to handle to get to a point where it could be studied by researchers."

National librarian Dr John Scally said: "This is one of the most challenging tasks our conservation team has faced and they have done a terrific job.

"Although significant sections of the map have been lost, the remainder has been cleaned and stabilised for future study and enjoyment.

"It would have been very easy for this map to end up at the bottom of a skip but thankfully it can now take its place among the magnificent maps held within our collection."