As we reported, Spink is holding an auction of rare stamps of China in Hong Kong on Sunday. Equal top billing has been given to a complete sheet of 80 8f stamps from 1980 which picture a monkey in honour of the Year of the Monkey for up to the equivalent of $52,000.

Usually, the thing with valuable stamps is that they are quite rare. So you wouldn't expect examples of a genuine rarity to come up for sale in the same month.

Yet extraordinarily, auctioneers Philip Weiss are selling a sheet of the same stamps for an online sale which - a 'Post Office Fresh' sheet. Philatelists will immediately notice differences in markings, not to mention numbering, between the two sheets.

Year of the Monkey stamp sheet

The estimate for the Philip Weiss sheet is $45,000-55,000, though it already appears to have bids narrowly exceeding this range.

The sale provides a fascinating comparison between the power of an online auction and a live auction, where the latter is taking place in the stamps' country of origin.