Cameo is a method of carving an object such as an engraved gem, item of jewelry or vessel made in this manner. It nearly always features a raised (positive) relief image; contrast with intaglio, which has a negative image. Originally, and still in discussing historical work, cameo only referred to works where the relief image was of a contrasting color to the background; this was achieved by carefully carving a piece of material with a flat plane where two contrasting colors met, removing all the first color except for the image to leave a contrasting background.
Cameo lockets are engraved lockets that feature raised relief image. The design style is in contrast with what we call intaglio that features a negative or etched image. Traditionally, a cameo locket only features an embossed image in contrasting color to its background. Following such practice it is common to see cameo lockets featuring women, dancers, sea horse, flowers among others crafted in silver or gold against a colored element.
Anyone will be able to appreciate the intricate design and the meticulous process in producing such beautiful lockets.