Even human error has a monetary value. Flawed stamps and coins have long been among the mostdesirable to collectors, and now mis-printed banknotes have their admirers.

As shown at Charles Leski's latest Coin, Banknotes, Stamps and Postal History auction (nowheld under the Mossgreen banner) an Australian banknote normally valued at $5 can be worth over$1000 if someone has accidentally stuffed it up.

This 1993 polymer note has a nominal value of $10 but because it is missing the intaglioprinting phase on the front - the final stage in the printing process, that adds the fine details,such as writing or complex artwork - it's now worth much more. Adding to its value, there'sno serial number on the reverse and the checker who spotted the error has added their ID number infelt pen.

Sold in "uncirculated" condition, it fetched $1220 IBP at the September 30 sale inMelbourne.

The question is, how do such obvious duds make it into the public domain?

Leski says that even in the polymer period the quality control of banknotes was initially doneby humans, so the occasional misprint passed through the system and escaped into the real world.Among enthusiasts, the magnitude of the error is what determines value at auction. Errors can rangefrom a missing serial number to, well, what you see here.

These are on the higher limits of the scale.

Condition is also important and these examples were obviously spotted early in their life-spanand handed over to someone who cared. Twenty years later and, bingo, their face value has jumped bymore than a thousand dollars in some cases.

Graham Shepherd is a pioneer in this specialist area.

A long-time collector and dealer in rare banknotes, he started to concentrate on error notes in1988 and has since discovered that others share this eccentricity. He estimates there are a fewhundred like-minded souls.

According to Shepherd the ones worth collecting are the bleedingly obvious, as in notes missingone colour or totally blank on one side. Examples of the latter also turn up on occasion.

Needless to say, if one appears in your spare change, keep it. What about counterfeit notes?Shepherd says these are also of interest to some collectors, despite the grey legality of owningthem.

"I won't say whether I have any or not," he says, "but yes, they are quitecollectable."

To read the complete article, see:
Note the errors, omissions and cash in (www.theage.com.au/money/investing/note-the-errors
-omissions-and-cash-in-20141010-1141ug.html)