In philately, an omnibus issue is an issue of stamps by several countries with a common subject and which may share a uniform design.
In the year 1920 a series of stamps were produced by for the small islands in the Cook Islands overseen by nearby New Zealand known as the Omnibus Issues of Cook Island. Aitutaki, a very small island in the Cook Islands, used the stamps of New Zealand and the Cook Islands with its own overprint for much of its history.
In 1920 stamps inscribed AITUTAKI were finally used for a short while of almost 12 years. Two pictorial sets were printed for the island, in 1920 and 1927, though these shared design elements with issues produced for nearby Rarotonga and Niue.
The 3 pence stamp came in the year 1920 was the first of the omnibus issue that bore the name of the country. The stamp depicted Rarotonga’s Avaruna Waterfront in centre under an arch inscribed with Aitutaki Postage with the denomination “Three Pence” inscribed in words flanked by the value in numerals.
On 15 March 1932, stamps of the Cook Islands again replaced the Aitutaki issues which were in circulation between 1932 and 1972. This ended with the establishment of a separate Aitutaki postal system, which began producing its own stamps.
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