The early history of the gem is quite obscure, though it probably belonged to Charles II, and was definitely among the jewels that his successor James VII and II took with him when he fled to France after the Glorious Revolution in December 1688.
As the last descendent of James VII and II, the cardinal put the sapphire, along with many other Stuart relics, up for sale. It was purchased by George III in 1807 and returned to the United Kingdom from Italy.
In 1909, during the reign of Edward VII, it was moved to the back of the crown to make way for the 317-carat (63.4 g) Cullinan II diamond; it still occupies that position in the back of the Imperal State Crown made in 1937 (a copy of Victoria's) and used by Elizabeth II.
The sapphire weighs 104-carat (20.8 g). It is oval-shaped, about 3.8 cm (1.5 in) long and 2.5 cm (1.0 in) wide, and has one or two blemishes but was evidently deemed to be of high value by the Stuarts. At some point a hole was drilled at one end, probably to introduce an attachment by which the stone could be worn as a pendant.
On the back is a miniature plaque engraved with a short history of the Imperial State Crown.
- Sir George Younghusband; Cyril Davenport (1919). The Crown Jewels of England. Cassell & Co. p. 57.
- Edward Francis Twining (1960). A History of the Crown Jewels of Europe. B. T. Batsford. p. 187.
- Claude Frégnac (1965). Jewelry from the Renaissance to Art Nouveau. Putnam. p. 109.
- "The Imperial State Crown". Royal Collection Trust. Inventory no. 31701.