This week, Bloomsbury Auctions is holding a sale slightly out of its usual comfort zone as it sends a private collection themed on Gibraltar under the hammer.

Consisting of 131 lots (which then carry on into a more general and separate auction of Travel, Natural History & Sport: Books, Maps, and Prints), it includes a large amount of scripophily and philately.

Although only a handful of the stamps offered are investment-grade, there are some interesting pieces for specialist collectors. For example, an early lot consists of a George V mint high values collection in an album.

This described as "a quite magnificent assembly of these lovely stamps" by the auctioneer (sadly, no picture is available).

This includes four plate blocks of 4 for the 2 shilling stamp, as well as one of 6 and two of 10 amongst a variety of others. The whole is expected to achieve up to £3,000.

The English Pilot map showing Puerto Rico

Top lot, however, may well be a copy of The English Pilot 'Describing The West-Indian Navigation, from Hudson's Bay to the River Amazones'

This includes a wide variety of engraved maps in the text (Barbados, Antigua, Bermudas) and woodcuts, with the contemporary signature of Samuel Brown applied to the title and again to the rear free endpaper.

A classic of its kind, the work is expected to achieve £15,000-£20,000 (up to $47,900) in Bloomsbury's sale which takes place this Thursday, July 14, in London. Given a continuing interest in historic maps and antique map-making the piece could make a strong alternative investment.

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