Antique Roman carnelian intaglio. An intaglio is a small gemstone, usually semi-precious, that has been carved with images or inscriptions only on one face, leaving a hollow impression in the untouched background. This style of carving is the opposite of the cameo technique. The engraving of gemstones was a major luxury art form in the ancient world and an important one in some later periods. This particular one is carnelian and dates from the second century AD and shows the head of a figure in profile. It is in very nice original condition and would be ideal for making into a ring.