Hard Stone
Only when grinding tools were constructed were they made from the harder chalcedony, cornelian and onyx.
The art form found its way from Egypt, through Assyria and into the Mediterranean countries through trade. Although the Egyptian craftsmen were productive, there was little creativity in their work. The Phoenicians, Etruscans, Greeks and Romans developed the art of gem engraving to the point that their seals became collectors' items.
The Mycenaean civilisation in Greece, Crete and Cyprus refined the craft to a high standard, but in the 12th century BC Mycenae fell, and the art of carving gemstones declined and was nearly lost. Revived by the Greeks between the 11th and 8th centuries BC, the scaraboid, a plain topped semi-oval, engraved only on the flat underside, appeared, at first crudely made. The craftsmen did not have the ancient Egyptian grinding tools, and had to work the hard stones by hand.
By the Golden Age of Greek classical art, from the 5th to the 4th centuries BC, the engravers had surpassed the skills of the Mycenaean culture. They worked in hard precious and semi-precious stones, choosing them for their colour and the ability to transmit light. They used, amongst others, chalcedony, jasper, cornelian, turquoise, and malachite.
Then, in the 3rd and 2nd century BC, the cameo, a carving in relief, was developed because of the introduction of many coloured, multi layered sardonyx from India and Arabia, at first thought to be synthetic. The cameo made a picture in the lighter, upper layers of the stone, standing out boldly from the lower darker layers. They used simple belt driven drills, carving finer details with hand held bronze or iron gravers.