In the absence of its original fitted case, it is difficult to attribute this necklace to any particular workshop but the quality of the mosaics would point to a date c.1860 and the subtle colouring of the portraits recalls Roman frescoes, the sitters evenly divided so as to face towards the centre, and when set in elaborate beaded wirework mounts the result is a tour de force of revivalist jewellery. For information on the many talented micro mosaicists working in Rome at this date see D. Petochi, I Mosaici Minuti Romani dei secoli XVIII e XIX, 1981. For a similar necklace, also unsigned, cf. Sotheby's London, 19 March 1987, lot 97