A portrait miniature of Lieutenant-General Charles Neville (1760-1837), painted by one of the greatest British miniaturists, artist John Engleheart (1750-1829), is to star at Bonhams come May 30.

Charles Neville was the illegitimate son of Edmund Rolfe (1738-1817) of Heacham Hall, Norfolk, and Julia de Martino of Lausanne, Switzerland

Estimated to be worth £8,000-12,000 ($12,000-18,000), the miniature features the general in his blue and red uniform, his hair powdered.

The detailed portrait is bordered by blue glass and framed with a double gold band; an intertwined lock of hair set with diamonds is just visible through a glazed aperture to the reverse.

Engleheart was a talented and prolific miniaturist. During a career lasting 39 years he produced 4,853 miniatures, which are considered highly collectible today. A leading example sold for £18,500 ($27,890) at Sotheby's in 2008.

Also to star is a rare portrait miniature by German-born painter Peter Eduard Stroely (1768-1826), featuring a young lady wearing a white dress and a burnt-umber stole, which carries a £6,000-8,000 ($9,100-12,000) estimate.

A rare portrait miniature by German-born painter Peter Eduard Stroely of an unknown young lady

A miniature believed to depict British romantic poet John Keats (1795-1821) will also feature, valued at £15,000 ($23,000).

Often small enough to be worn as jewels, portrait miniatures served as keepsakes, as well as a means of introducing potential suitors to one another.

A nobleman seeking a suitable suitor for his daughter might send a courier equipped with her portrait miniature to visit those young men he deemed apposite, while soldiers and sailors may have kept miniatures depicting lovers and family members with them when travelling.

For information on the investment potential of the art market, see Paul Fraser Collectibles' free guide to investing in art and photography.

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