Spink recently held a sale of world banknotes in London. Banknotes sometimes don't receive as much attention and enthusiasm as coins, but this auction showed just how keen notaphilists (banknote collectors) can be.

Many lots proved to be profoundly underestimated as time after time a fury of bidding broke out over the finest pieces.

The day started briskly, with a South Australian 1 August 1879 specimen black, white and pink £20 note selling for double its £4,000-6,000 estimate at £10,000 (not including buyer's premium).

Soon, the bidding picked up still further, with a tan booklet stamped with Rs 5 in red containing 17 specimen 5 Rupee notes quadrupled its highest expected price of £3,000 for a hammer price of £12,000.

Things really heated up however when a prize selection of Iraqi banknotes reached the stage. Whether simply due to an increased interest in the history of the region or Iraqi collectors wishing to bring back some of their history, the bids came in thick and fast.

Two 1941 100 dinar notes in excellent condition displaying King Faisal II as a child easily exceeded their estimates with a specimen note similarly quadrupling its top estimate of £3,000 to sell at £12,000, and a green colour trial of the same denomination fetching £15,000.

King Faisal II 100 dinars colour trial

The other two strong performers of this section of the sale depict King Ghazi in specimens of another design of 100 dinar notes. Both have the date 29.7.36 inked in. Both are fresh, attractive, almost extremely fine pieces. Both had listings of £2,000-3,000 which those attending flatly ignored.

One depicts Ghazi as a young man in profile in the blue circular background and bears the serial number A005251 - A007250. It tripled its top estimate and taken home for an impressive £9,000 (plus buyer's premium).

King Ghazi 100 dinar banknote

This was completely eclipsed by the other note, however, which presented Ghazi in a moustached portrait and bears the serial number A000001-A003750. A fury of excited bidding broke out, and the price shot upwards, with the winning bidder's last competitors only bowing out at £26,000.

The note's sale is an excellent example of how increased interest in a country is reflected in the value of its collectibles.

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