Natural Science in Archaeology

188 8 Ceramic Raw Materials
dominant clay minerals in shales and mudstones. They also form commonly in soils
from the alteration of micas and other clay minerals and from colloidal silica. Illite
is the only clay mineral containing appreciable amounts of potassium. In soil-forming
processes, illite apparently can form from montmorillonite by exchanging all
the exchangeable cations with potassium.
Illite forms small, poorly defined flakes, commonly grouped together in irregular
aggregates. This type of clay has a luster that makes it sought after for pottery slips
(e.g., Greek black figure ware). Illites are characteristic of offshore marine deposits.
They are common in calcareous sediments. Grim et al. (1937) proposed the term
illite as a general term, not as a specific clay-mineral name, for the mica-like clay
minerals. The name was derived from an abbreviation for the state of Illinois.
The dominant clay mineral in most shales is illite, but montmorillonite is common
in shales of Mesozoic or younger age. Kaolinite is common in some shales.
Kulbicki (1954) concluded that diagenetic changes in the sediments of the Aquitaine
Basin in France produced kaolinite and halloysite from nuclei of other clay minerals,
and that montmorillonite formed from halloysite or formed together with halloysite
from kaolinite. Therefore, we can see that most clay deposits are mixtures.
Soils developed under cool and damp climatic conditions with forest or grass
cover provide an abundant surface accumulation of organic material. Kaolinite predominates
in these soils, and illite is frequently present. In the soils of arid regions,
montmorillonite and illite predominate. Illite is the dominant clay mineral in sediments
accumulating in Lake Erie in North America (Cuthbert 1944). Sarmiento and
Kirby (1962) reported kaolinite, illite, montmorillonite, and chlorite in the sediments
of Lake Maracaibo in South America.
8.3 Pottery
Along with lithics, pottery fragments are the most widespread traces of human
occupation. Most ceramic studies concentrate on the reconstruction of descriptive
technologies in order to establish temporal sequences and cultural boundaries.
The first pottery dates back 8500 years and probably was a traded product well
before 6000 BCE (Mellaart 1964). The development of European and Near Eastern
pottery is a major story that cannot be repeated here. In North America, pottery
developed much later, coincident with the transition to farming and settlements. The
earliest ceramics probably come from the southeastern United States about 2000
BCE. In South America, pottery may have developed somewhat earlier, about 2500
BCE (Meggers and Evans 1966). By the late first millennium CE, Mayan potters
had developed exceptional skill.
The Chinese, always inventive artisans with bronze and jade, were also excellent
ceramists from the Neolithic onward. Nearly all of the eastern (populated) areas
of China have almost unequaled resources of suitable raw materials for pottery
production. The Chinese have long excelled in both low-fired earthenware and highfired
stoneware and porcelain. Neolithic earthenware from east central China is a