Australia Official OS Stamps

Australian Official Service or OS stamps, introduced in 1902, were punctured or overprinted OS for use in Federal Government departments. Their use was to signify the mail was for official purposes and presumably to try to stop fraudulent use of the stamps by employees.

The first punctured or 'perfin' stamps were were punctured with a large size OS but the holes weakened the stamp so that the perfins were reduced in size to a smaller OS from about 1913 onward. A medium size OS was used in 1927-29 on three commemorative issues. There is also what is referred to as the NSW perfin as the "S" of "OS" had 12 holes, as compared to 11 found in most small OS; this only used for New South Wales state departments.

	Perfin	Dates/Issues	Size
	Large OS	1902 to 1914	14mm high, 15mm wide with 19 holes in "O" and 17 holes in "S"
	Medium OS	1927 Canberra, 1929 Western Australia Centenary &1929 Airmail	10mm high, 14mm wide with 12 holes both in "O" and "S"
	Small OS	1913 to 1930	7.5mm high, 15.5mm wide with 12 holes in "O" and 11 holes in "S"

The perfin was replaced by an overprinted OS in 1931 and the use of the OS was withdrawn in 1933. Maybe the employees were stealing them for their collections!

Missing Colours / Colors on Stamps

One of the most frequent requests we have, at our site for Australia Stamps Steve Irwin Stamps, for help on identifying stamps is on potential missing colours /colors from stamps. The individual hopes they have found a new missing colour that has not yet been identified or catalogued. Unfortunately, we have to disillusion the individual most of the time.

The chances of finding an unidentified missing colour is remote. Colours can be lost through fading in the sun or chemical treatment. Chemical treatment on used stamps, where there is no gum is very difficult to detect, especially without specialist equipment. Colours can also be faded in the sun either deliberately or accidentally. Individuals are often misled because one colour appears to be missing while the other colours look the same as the original; colours ranges fade differently; the red/orange range will often fade when blues and greens are not affected. See the example below where the orange tone seems to be missing from the right-hand stamp, with the yellow and greens looking the same as the original on the left - this has happened as a result of fading.

Stamps where the colours that have been changed subsequent to being printed are known as "colour changelings".

To summarise, that stamp you think is missing a color is much more likely to be the result of treatment or fading. However, if you are not convinced by my arguments and you want to "prove" your missing colour, what should you do?

1. Look at the stamp under a UV lamp (if you don't have one take the stamp to a local dealer and ask them to look at it for you). Signs of fading usually show under UV, the stamp will look "duller" than an ordinary stamp in the same situation. However, even if it doesn’t it still doesn’t prove it is a genuine missing colour.

2. The next step would be to send it to be expertised by an expert committee. In the UK there are several bodies who do this including the Royal Philatelic Society who charge £30 for this service. In the States, committees include the American Philatelic Society, who charge an initial $25 for this service (but needs to go through a member) or The Philatelic Foundation with an initial fee of $27. You need to pay the fees whatever the outcome, so you are probably wasting your money - but don't say I didn't warn you!


Genuine missing colours can make a very attractive and interesting collecting area. Missing colours are listed in specialist stamp catologues or in Pierron's Book or website on Modern Great Britain & Commonwealth Missing Colour Errors. An example of a genuine Australian missing colour is the missing grey on the 1986 36c America's Cup Triumph - pretty spectacular!

Australia Maximum Cards

Australia produces maximum cards for all its main issues of stamps. For those unfamiliar with the term, maximum cards are postcards depicting a scene related to the stamp and usually postmarked on the first day of issue of the stamp. The stamp and postmark are usually placed on the picture side of the card to heighten the effect of the theme.

Australian maximum cards are great for thematic collectors as they effectively give a postcard size picture of the stamp theme. Australia maximum cards cover a large range of birds and animals as well as famous people, cars, trains boats etc.

Australia Stamp Reprints

Another question that comes up quite often is, what are the koalas and kangaroos on Australian stamp margins for?

These are referred to as Australia Stamp Reprints. The marginal emblems (koalas and/or kangaroos) were added to Australian stamps in 1988 and continue to today. These are put on to the stamp sheets by the printers to identify a reprinting of a current stamp. These usually occur in definitive sets which are in use over several years and may have several printing and also may have been printed by more than one printer. The first print has no marking, the second one koala emblem, the third two koalas and so on. The sixth printing is marked by a kangaroo, the seventh by a kangaroo and a koala, the eight a Kangaroo and two koalas. The current largest number of printing is nine with a kangaroo and three koalas found on the 20c 1997-98 Nature of Australia, Kakadu Wetlands series.

The emblems are very collectible. They occur either on the left or right side of the stamp and there are currently about 250 different stamp and emblem combinations avaiable.

Full list of reprints.

Australian Stamp Identification

Have you inherited or have some stamps from Australia that you are not sure what they are? If so, we would be happy to have a go at identifying them for you and give advice about selling prices and how to sell your stamps.

If you would like an individual stamp or set or philatelic item from Australia identified please scan the item and e-mail the scan to Steve Irwin Stamps (small size scan and individual stamps only please) and we will do our best to identify it for you!