The oldest known jewels are amber, nephrite, garnet, rock crystal, amethyst, serpentine,emerald and pearl. Others may have been used but are not yet found in archaeological excavations.
Cylindrical seals (which worked by rolling them along in soft clay, to sign your name)from Babylon and elsewhere were made from soft varieties of soapstone or steatite, serpentine and marble. Soapstone is very soft and easy to carve. Later lapis lazuli, hematite, amazonite, jasper and rock crystal were used. This suggests that they increasingly used attractive stones for their seals rather than just functional ones.
The Egyptians carved intaglios and scarabs from carnelian, chalcedony, green jasper, lapis lazuli, amazonite, amethyst, turquoise, emerald and ruby. Greeks and Romans carved figures from amethyst, rock crystal, carnelian and jasper. Jewels were set in gold and silver in the Early Bronze Age. Please note - no diamonds!