The art of engraving gemstones can be traced back to ancient Greece in the 8th century BC and earlier. Techniques passed down to the Egyptians and then to the Romans. There were major revivals of interest in engraved gems in Europe during the Byantine era, the Middle Ages, the Renaissance, and again in the 18th and 19th centuries. At each stage cameos and intaglios, these skillful carvings on a minute scale, were much prized and collected, sometimes as symbols of power mounted in jewelled settings, sometimes as small objects for private devotion or enjoyment. This imitation engraved gemstone is in the neo-classical style popular in the late 1700s and early 1800s, when taste in the arts echoed the subject matter and style of the Greek and Roman masters. Thousands of gems were made in this style in Italy and brought back by British Grand Tourists, who went there to visit the newly-discovered classical antiquities and archaeological sites. This particular form of reproduction is known as a 'doublet'. The care with which it has been made, and then mounted in gold, shows how desirable engraved gems were. A glass paste mould of a classical head has been stuck to a real jasper backing to reproduce the effect of a genuine engraved gemstone with two layers of colour. This portrait resembles heads of the Roman emperor Claudius (10 BC-54 CE) on coins from his reign.