Mermaids seen due east as rare maps go on sale

An atlas drawn in 1593, complete with mythical creatures, could fetch more than £500,000

Maps in the 1593 Speculum Orbis Terrarum by the Belgian cartographer Gerard De Jode

One of the world's rarest atlases will go on sale in London next weekend and is expected to fetch over £500,000.

The full-colour Speculum Orbis Terrarum was produced in 1593 by the Belgian cartographer, Gerard De Jode. One of only two in the world, it will go on sale at the London Map Fair, held at the Royal Geographical Society in central London.

It is being sold by New York collector Bob Augustyn. A full-colour De Jode atlas is thought to have come up for sale only once in the past 50 years. That was sold by Lord Wardington of Oxfordshire for almost £300,000, in 2005, and was said to be in a poorer condition than this one.

De Jode's atlas was incomplete at the time of his death in 1591, his son Cornelis finishing the project. Tim Bryars, a dealer in antique maps, said: "I'm absolutely thrilled to see a second copy of this atlas in the market place. This is the expanded edition of the atlas and is in a beautiful condition."

Despite the maps being incredibly lavish, they never made the map makers much money.

Fantastical decorations on the maps include, in the case of New Guinea, a dragon and hunter, a rearing lion, and a merman and mermaid embracing in the waves.

"There has never been an easy way of making money from maps," said Mr Bryars. "They are incredibly labour-intensive to produce – the cost of commissioning these surveys and creating the network of people to supply you with the information, and producing the copper plates to print, was very expensive."

The map is an enlarged edition of De Jode's original 1578 atlas which was produced with the aim of competing with a former collaborator, Ortelius, who had published Theatrum Orbis Terrarum in 1570.

This atlas had become so popular by the time De Jode's own work was published, that the latter never sold well despite scholars' claims that it is one of the best of its time in both detail and style.

The value of words

* The world's most expensive book, at £7.3m, is John James Audubon's Birds of America (Sotheby's, 2010)

* A 1925 first edition of The Great Gatsby is to go on sale in London later this month for £120,000

* An 1847 Jane Eyre is this month set to make £50,000 at Bonhams

* A collection of Joseph Conrad first editions, inter alia, is set to fetch up to £500,000 at Sotheby's in July

* A first folio Shakespeare sold at Sotheby's in 2010 for £1,497,250

Katy Guest