Roman Jewelers And Lapidaries

(via Roman Book On Precious Stones: 1950) Sydney H Ball writes:

As to the cutting of gems, Pliny states that cut stones with a smooth level surface are preferred to those which exhibit depressions or other irregularities. An oblong shape is best; next to it, the lenticular; after this, circular stones are admired, those which are irregularly angular being held in the least esteem. In explanation, flat stones were preferred to those capable of being cut only cabochon, as the former were suitable for engraving. The oblong had evidently supplanted the ancient lenticular form while the angular was perhaps only used when to cut the rough gem in one of the more desired forms would drastically reduce the weight of a stone. The only stone Pliny mentions as faceted was the beryl (and its variety emerald) and this only by polishing the six faces of the natural prism; a method believed to be the best to increase the stone’s brilliancy. The Hindus, in Pliny’s stime, preferred long hexagonal beryl beads and these, pierced, were strung on elephant’s hair, it being the only stone they wore without gold setting. The piercing evidently improved the color adn transparency of some beryls although the finest were not pierced but were held in place by studs of gold attached to the ends. Beads of plasma and garnet also cut into prisms are from time to time found in Roman ruins, so abundantly indeed that graded necklaces can be made from them. These presumably postdate Pliny’s time. The sardonyx was also pierced and worn in neck ornaments by the poorer people of India. In Pliny’s time, the presence of a hole pierced in the stone proved it of Indian origin, an indication still in instances used by precious stone dealers. The lapidaries of the day hollowed out the lower side of garnets of deep color to give them a lighter and more pleasing hue. While shaped into cups, garnet ‘offers the most obstinate resistance to the graver’. Other stones were most easily cut, that of the callaina (turquoise) being ‘easily done’. Topazos (peridot) is the ‘only stone of high value that yields to the action of the file, the rest being polished by the aid of the stone of Naxos’ (emery). Peridot ‘wears with use’, its softness being the reason why we today rarely set it in rings. Unusually perfect rock crystals called acontetta (without flaw) were set uncut in jewelry.

Pliny states that the skilled artisan can hide the imperfections of rock crystal by cutting and engraving the stone. Tavernier, sixteen hundred years later, warned merchants to examine, with particular care, Indian diamonds with many facets, for the Hindu diamond cutter hid flaws with facets.

The garnets found on the hill of Orthosia in Asia Minor were cut ‘to perfection by the Alabandians’ in the nearby city of Alabanda. The early existence of this cutting center, exclusively for colored stones, is interesting.

Softer stones were shaped by a file but emery was used to cut and polish most gems. The emerald and the sapphire were rarely engraved and, as to the latter, the lapidary usually only polished the surface of the original pebble.

Pliny lists as famous engravers Pyrgoteles, Apollonides, Cronius, and Dioscurides, all Greeks. Alexander the Great permitted Pyrgoteles alone to engrave his likeness. Dioscurides cut a signet with an excellent likeness of Emperor Augustus, a seal thereafter used officially by the Roman Emperors. Gem engraving reached its height under Augustus adn continued on a high plane until the time of Hadrian when it began to deteriorate. Indeed, in general, the decline of classical art appears to have been more or less continuous from about 400 B.C to 200 A.D.

Seneca is the first Roman to speak of cameos (to be specific, a ring set with the head of Tiberius in relief), intaglios having preceded them by thousands of years. A few cameos, however, were cut in Greece and in Etruria early in the 5th century B.C but cameos only became relatively common a couple of centuries later when Indian layered stones were available to the Greek lapidaries. The Babylonians, centuries before, had rather crudely cut a few poor cameos. In Rome cameos which could only be used ornamentally, were never as popular as intaglios which were not only beautiful but also had their practical use as signets.