Great Britain 1856 4d carmine on thick blued highly glazed paper Plate 1, SG63s Grenada stamps Zanzibar 1891 (AU 10) cover

Zanzibar 1891 (AU 10) cover FRONT to 'Basil Wood Walker

XII behind

Slight horizontal crease

mixed perforations 10 and 12½

Great Britain 1856 4d carmine on thick blued highly glazed paper Plate 1, SG63s Grenada stamps Zanzibar 1891 (AU 10) coverGreat Britain 1856 4d carmine on thick blued highly glazed paper Plate 1, (Watermark Medium Garter), SG63s. A superb unmounted mint bottom marginal block or four showing part sheet inscription, overprinted "SPECIMEN" type 2 vertically. A stunning quality scarce position piece. "SPECIMEN" examples were used solely by postal administrations for reference purposes to help spot any attempted forgeries. GB Specialised Catalogue No: J48 (2)t. Stanley