Turquoise occurs in shades of pale blue through greenish blue to green. The most highly prized colour is a deep sky blue, the best quality of which usually comes from Iran. The blue colour is caused by the presence of copper. Green tints develop with the presence of iron. Turquoise is a porous material, prone discolouration by the absorption of oils from the skin or from perfume. This ring is set with strips of gold wire which appear to be Arabic text but are purely ornamental.

This ring forms part of a collection of 760 rings and engraved gems from the collection of Edmund Waterton (1830-87). Waterton was one of the foremost ring collectors of the nineteenth century and was the author of several articles on rings, a book on English devotion to the Virgin Mary and an unfinished catalogue of his collection (the manuscript is now the National Art Library). Waterton was noted for his extravagance and financial troubles caused him to place his collection in pawn with the London jeweller Robert Phillips. When he was unable to repay the loan, Phillips offered to sell the collection to the Museum and it was acquired in 1871. A small group of rings which Waterton had held back were acquired in 1899.