Queen Elizabeth II. Royal Jewels |Coronation Jubilee|Queen Adelaide's Brooch| King William IV Diamond Brooch

The diamond brooch was made by Rundell to the order of William IV as the clasp for a large pearl necklace for Queen Adelaide, using stones taken from a jewelled Badge of the Order of the Bath that had belonged to George III.

So it was also called King William IV Diamond Brooch.With six large brilliants in cut-down open-back collets, set in a hexagon framed by brilliant-set fleurs-de-lis surrounding a large brilliant encircled by 12 smaller stones.

The stones were delivered to Rundell on 17 December 1830, and the clasp was complete by 1 February 1831. The necklace for which it was intended was probably that worn by Queen Adelaide for the coronation on 8 September 1831 and shown in her coronation portrait by David Wilkie .

The clasp (with the pearl necklace)was among the jewels returned by Queen Adelaide following William IV’s death,
and it is next recorded in 1858 (as a brooch or snap) in Queen Victoria’s inventory of jewels belonging to the Crown.

The description and provenance are repeated more fully in 1896, and as a brooch it has subsequently been worn by Queen Alexandra (at her waist), Queen Mary (occasionally with a pear-shaped pendant attached) and
Queen Elizabeth (as a corsage brooch).

With other heirlooms of the Crown, it passed to The Queen from Queen Elizabeth, the Queen Mother, after the death of King George VI in 1952.

QUEEN ADELAIDE was the elder daughter of the reigning Duke of Saxe-Meiningen, a small Saxon duchy in south-west Thuringia adjoining Saxe-Coburg, and was married to George III's third son, the Duke of Clarence and future William IV, in 1818. She was one of three royal brides selected in considerable haste for the unmarried royal dukes (of Clarence, Kent and Cambridge), in order to secure the succession to the throne of Great Britain following the untimely death of the Prince Regent's only child and heir, Princess Charlotte (1796 -1817). The Duke of Clarence succeeded to the throne as William IV on the death of George IV in 1830. While personally of modest and retiring disposition, Queen Adelaide enjoyed wearing jewellery, especially the magnificent pearls and diamonds that had belonged to her mother-in-law, Queen Charlotte; and she had clear ideas of the jewellery appropriate for a queen consort. In preparation for the coronation of 1831, she firmly rejected the old-fashioned and dilapidated consort's crown and diadem of Mary of Modena, requesting instead a new queen consort's crown, for which she provided stones from her own jewels, and for which (at William IV's insistence) she paid herself.1 William IV was well aware of public demands for retrenchment and econ- omy after the excesses of George IV's reign, and therefore sanctioned only limited expenditure on jewellery. This consisted, for the most part, of the remodelling of family diamonds for Queen Adelaide, mainly using the stones taken from insignia that had belonged to his parents, George III and Queen Charlotte.

As the consort of George IV's successor, Queen Adelaide was also the first female member of the royal family to wear the Diamond Diadem , a piece of jewellery that had been made for George IV's use at his coronation in 1821. Since 1830, the diadem, which was undoubtedly the most distinguished surviving piece from George IV's extensive jewellery collection, has been worn only by queens regnant and consort