Karim Arafat and Catherine A. Morgan
David William John Gill
Petrographical and chemical analysis are the two main ways to characterize pottery. The former treats the pottery as a geological sediment which has been used for a particular purpose. Thus by scanning thin sections of pottery under a polarizing microscope, mineral inclusions can be visually identified; this allows a parallel to be drawn with other ceramic material, which may lead in turn to an identification of the clay source. This technique is particularly useful for coarse wares such as transport *amphorae. However in the case of fine pottery where inclusions have been removed, the clay can be treated as a bulk material. The sample can be studied by three main means: neutron activation analysis, optical emission spectroscopy, and atomic absorption spectrophotometry. In addition to the three main elements within clay (silicon, aluminium, and oxygen), an analysis will seek to determine the percentage of other elements in the composition: iron, calcium, magnesium, potassium, sodium, and titanium. These proportions can then be plotted and the results compared with other tests from pottery or indeed from clay sources.
O. T. P. K. Dickinson and Simon Hornblower
Frederick Norman Pryce and Michael Vickers
Rings were used in Minoan and Mycenaean times (see
Donald Emrys Strong and Susan E. C. Walker
Frederick Norman Pryce, Donald Emrys Strong, and Michael Vickers
Seals played an important part in ancient life, taking the place of the modern signature on documents and, to some extent, of *keys and locks. The materials for sealings were *lead and wax for documents; in commerce a lump of clay was commonly pressed down over the cordage. In Roman times small seal-cases were frequently employed to protect the impression from damage. The seals themselves were generally of stone or metal, sometimes of *ivory, *glass, and other materials; some early seals, pierced by string holes, were worn round the neck or wrist, but ancient seals were frequently worn as signet *rings.
The use of seals began in neolithic times in Greece and they were in common use in EH. Seals of ivory, hard stones, and precious metals were made in Crete where they appear in EM II; the two main types were the stamp and the cylinder seal; the finest Minoan and Mycenaean seals were cut in hard stone and precious metal. The techniques of cutting stone seals were revived in the later geometric period, the most notable series being the so-called Island Gems; hard stones—chalcedony, cornelian, rock crystal, and others—were used again from the middle of the 6th cent. The scarab form which had been popular in Egypt from the ninth dynasty was adopted in Archaic Greece and the scaraboid was the commonest form in the 5th cent. Gold signet rings were also popular.