A rare specimen Gibraltar £50 is among the highlights of a major sale of world banknotes at Spink London on September 28-30.
The note displays the serial number B000000
The lot, which displays the serial number B000000, was produced as a mock up and never released into circulation.
It's valued at £15,000-20,000 ($20,053-26,738).
Spink's banknote expert Barnaby Faull noted: "It doesn't seem so long ago when I was a young man (to many of you I still am!) and the banknote department was grudgingly allowed a few banknote lots at the end of a coin sale, how things have changed.
"This time, it seems we have been cataloguing from dawn to dusk for the last few months and we have three magnificent catalogues to show for it."
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