1859: THE ERROR OF COLOUR. The piece bearing the unique dated example of
the 1/2 grana printed in “deep dull blue” instead of orange from Plate II, with
large margins all round and cancelled by the framed handstamp in black.
Palermo datestamp at right (April 21, 1859). A philatelic world rarity.
This famous stamp error of colour was ably recorded by Emilio Diena in 1904:
“the person who found the letter in Syracuse was a collector. He detached one
of the specimens from the letter and put it into his collection. The letter was
then sold to a Parisian dealer, from whom the other error (the loose copy) was
re-sold to Prince Doria Pamphilj and this copy was exhibited in Manchester at
the Philatelic Exhibition of 1899”. Diena goes on to state that the stamps were
probably accepted as 2 grana paying double the inland rate, as when he
originally saw the piece it was larger but nevertheless had no trace of a
charge mark in manuscript on it.

Sold by Galerie Dreyfus on 6-10 June 2011 for €1,800,000