Thank you for submitting your item for appraisal. This necklace is composed by a chain and a round shaped pendant, both in white metal. The pendant has a white metal frame which is surrounding a black glossy material. In the middle of the black slide there is a three-dimensional female face in profile which is also in white metal and it remembers the traditional design of a cameo. The black material appears like an opaque glass slice, since there is no evidence of color gradient on any of the sides. The pendant is stamped "1275" on its back, which is not a known hallmark. Observing the pictures, the metal looks a shiny silver color, not tarnished. According the color of the metal and the general aspect of the item, it is probably made in alpaca silver, an alloy of copper, nickel and sometimes zinc or iron. Alpaca silver is also known as German silver and it has been used for since the 1823. Analyzing the photographs, it is probable that the object dates back to the Victorian era.
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Thank you