These earrings are set with layered agate cameos, imitating ancient masks. They were made by the firm of John Brogden (1820-1884) and shown at the International Exhibition, Paris in 1867. The industrialist Henry Bolckow (1806-78) visited the Exhibition and bought these earrings for his wife Harriet. Henry Bolkcow (1806-78) , a naturalised German, had made his fortune in the iron industry. He became the first mayor of Middlesbrough, a member of Parliament and a local philanthropist. Harriet Bolkcow survived her husband and on her death in 1890, left a group of assorted jewels and her collection of lace to the South Kensington Museum (now the V&A).

The earring with the mask carved in an almost white layer of agate follows a design (E.2:1221-1986) in the 'The Brogden Album' now held in the Print Room of the V&A. In an essay on the album published in the auction catalogue when the album was sold by Sotheby's (5 December 1985, lot 411), Shirley Bury attributed the design for the earring to Mrs Newman, who designed for Brogden for many years. After his death she set up her own shop and workshop. The album contains 1,593 designs for jewellery and goldsmith's work, mainly in colour and dating between 1848 and 1884. It is a unique record of the years in which John Brogden, an internationally celebrated 'art goldsmith and jeweller worked first in partnership and then as owner-director of his own firm. This was a period of great diversity in fashionable jewellery, and the Brogden firm where noted for their skill in designing and creating a range of styles.

The firm was founded by John Brogden the elder in about 1796. From about 1824 to 1831 it was styled 'Brogden and Garland' and thereafter until 1841 'Garland and Watherston'. The younger Brogden, the son of Thomas Brogden and presumably a relative of the founder, served an apprenticeship to J.W. garland as a goldsmith and jeweller from 1834 to 1841. Following Garland's departure, the remaining partner, J.H. Watherston, removed the firm to new premises at 16 Henrietta Street, Covent Garden and in 1848 joined forces with the younger Brogden.