The Hanoverian rulers of Great Britain gathered a large collection of personal jewellery and Queen Charlotte, the Consort of King George 111, was certainly no different. She received many jewels, the most remarkable being the diamonds she received from the Nawab of Arcot. These included five brilliants, the largest of which weighed 38.6 carats, was oval-shaped and later set in a necklace with the two smallest stones. The other two diamonds were pear-shaped and were set as earrings; one weighed 33.70 carats and the other 23.65 carats. These two have become known as the 'Arcot' diamonds.
Arcot, a town near Madras, became famous for its capture and defence by Clive in 1751, during the war between the rival claimants to the throne of the Carnatic. It passed into British hands in 1801 following the resignation of the government of the Nawab Azim-ud-daula, who had given the diamonds to Queen Charlotte in 1777.
The Queen died in 1818 and under the terms of her will the 'Arcots' were ordered to be sold to Rundell & Bridge, who in 1804 had been appointed jewellers and silversmiths to the Crown by George 111. The clause about her 'Personals' read:
...of chief value being the jewels. First those which the King bought for £50,000 and gave to me. Secondly those presented to me by the Nawab of Arcot.....I give and bequeath the jewels received from the Nawab of Arcot to my four remaining daughters or to the survivors or survivor in case they or any of them should die before me, and I direct that these jewels should be sold and that the produce .....shall be divided among them, my said remaining daughters or their survivors, share and share alike.
However a delay arose in implementing the Queen's will. This was the result of the attitude towards the will taken by her eldest son, George IV who, upon the death of his father in 1820, decided that the whole of his father's property would pass on to himself, not upon the Crown. Consequently he took posession of money and the jewels and acted in a similar manner with regard to his mother's jewellery. The 'Arcots' were, therefore, set in the crown made for George IV and later in the crown made for Queen Adelaide, the Consort of his Successor, William IV.
The terms of Queen Charlotte's will concerning the items of jewellery were accordingly not executed until many years after she had died. In 1834, John Bridge of Rundell & Bridge died; the firm was sold and his Executors ordered the sale of the 'Arcots' together with the round brilliant, which may have been the 'Hastings' diamond and which had also been set in the crown made of George IV. The important sale in history took place at Willis's Rooms in London's St James's on the 20 July 1837. The first Marquess of Westminster bought the 'Arcots' for £11,000 as part of a birthday present for his wife; he also bought the round brilliant and the 'Nassak' diamond.
The 'Arcots' and the other diamonds remained in the possession of the Grosvenor family for many years. In 1930, the Parisian jeweller Lacloche mounted the 'Arcots' in the Westminster Tiara, of bandeau form, together with the round brilliant and no less than 1421 smaller diamonds. The tiara was pierced to form a design of pave-set scrolls with arcading, and with clusters of navett-shaped diamonds between the sections, tapering slightly at the sides, with baguette diamond banding framing the large centre stone and with diamond baguettes scattered singly throughout the ornament. In her memoirs, Loelia, Duchess of Westminster, third wife of the second Duke, wrote of the 'Arcots', 'fixed by themselves on the safety-pin they looked extremely bogus, so that a friend who saw me that evening remarked, "What on earth does Loelia think she's doing, pinning those two lumps of glass on herself" (the diamonds could be removed from the tiara and worn separately as earings).
In June 1959, the third Duke of Westminster sold the Westminster Tiara to help meet the cost of heavy death-duties. Harry Winston paid £110,000 for it at the Sotheby's auction - then a world record price for a piece of jewellery. Subsequently Mr Winston had the two 'Arcots' recut to obtain greater clarity and brilliance, the larger to 31.01 metric carats and the smaller to 18.85 metric carats. Each was remounted as a ring and sold to American clients in 1959 and 1960 respectively.