Indian rupees, later in Gulf rupees, being overprinted to be used in Bahrain, Kuwait, Qatar and the Trucial States. In Tangier, Morocco, the three Castle stamps were available at the British post office in 1955. When the office had to be closed in 1957, its centenary was celebrated with a second overprint ("1857 - 1957") on all Wilding and Castle stamps. Some Castle stamps are known without the hyphen or with one printed thanks to a third overprint. Commemoratives On 22 March 2005, Royal Mail issued a minisheet for the 50th anniversary of the Castle series. Denominations were changed to 50 pence for a brown "Carrickfergus Castle" and a dark brown "Windsor Castle", and one pound for a red "Caernarfon Castle" and a blue "Edinburgh Castle". The Dutch printer Enschedé succeeded in using the original dies to create the new printing material, but for the Windsor Castle stamp digitalization of a 1955 stamp was necessary. The 1988 series Description On 18 October 1988, the four large-format high value Machin stamps, printed in photogravure and issued since February 1977, were replaced by a new Castle series. The four new stamps were printed in intaglio, and their illustrations were based on photographs taken by Prince Andrew. The profile of Queen Elizabeth II appeared on one of the upper corners, and was based on Arnold Machin's sculpture that appears on the Machin series. The same castles were used as for the 1955 series: Carrickfergus on a £1 green stamp, Caernarfon on the £1.50 brown, Edinburgh on the £2 blue and Windsor on the £5 brown. The broken grotto design was replaced by a white background, and was considered austere compared to the romantic approach of Lyndon Lamb. Career In 1992, the series was reissued with two changed elements, in order to fight counterfeiting. An elliptical perforation was added to the sides, and Optically Variable Ink (OVI), which appears green or gold depending on how it is viewed, was used to print the Queen's profile. The latter was no longer the Machin head with crown, but the monocolour profile created by Machin for commemorative stamps. In 1995, the £1 Carrickfergus Castle stamp was reissued with a new denomination of three pounds, because inflation no longer justified the use of an expensive printing method like intaglio for the one pound value. A £1 Machin definitive stamp was created the same year, printed in a blue-violet