Half-arch (crowns)

A half-arch is the piece of gold, silver or platinum, usually decorated with jewels, that links the circlet (circular base) of a hoop crown to the monde at the top of the crown.

In the image of the Crown of Queen Elizabeth (1938), there are four half-arches, reflecting the examples of St. Edward's Crown, the State Crown of George I, the Coronation Crown of George IV and the Imperial State Crowns of Queen Victoria (1838) and George VI (1937).

Similarly other consort crowns of queens consort Mary of Modena and Adelaide of Saxe-Meiningen, the Crown of Mary of Modena and the Crown of Queen Adelaide, were made up of four half-arches, following British tradition.

The only example of a crown of a reigning British monarch possessing more than four half-arches is the Imperial Crown of India, made for King George V as Emperor of India to wear at the Delhi Durbar of 1911, and which had eight half-arches.

The three crowns in existence of the Prince of Wales, the Heir Apparent to the British throne, all have one full arch, with a globe centred on the single arch rather than being the element to which each arch separately is joined, following an instruction laid down by King Charles II in 1677. Unlike the princely crowns of 1902 and 1969 however, where the single arch rises, in the Crown of Frederick, Prince of Wales (1728) the single arch dips in the centre, with the globe located in the centre of the dip.

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