Nile clay

Below Unit B a silty sand layer (Unit C) was encountered in the cores taken between the mouth of the Great Wadi and the center of the Kom el Ahmr. Unit C contained a sequence of Old Kingdom to late Predynastic artifacts dating from about 2500 B.C. to 3200 B.C. Below Unit C, a very compact, well-sorted thick layer of Nile clay and sand was encountered (Unit N). No cores or trenches reached below this sedimentary deposit. Unit N contained occasional Predynastic ceramic and flint artifacts. Samples were collected from each 10-15-cm auger cut within each sedimentary unit in each core or trench. In addition, numerous samples of the Neonile deposits and other sediments from the nearby low desert and Great Wadi were taken for analysis. 

Finally, as chemists and archaeologists, it is interesting for us to be able to demonstrate, with a variety of analytical techniques, that while the early Egyptians of Hierakonpolis were transforming their society into the world s first politically centralized nation-state, they were also recognizing the utility of natural materials to aid them in transforming humble Nile clays into new forms of economically, artistically, and symbolically important ceramics. 

The Necropolis of Antinoe is located about 9.5 km south of Beni Hasan, in a village called Sheikh Abada, on the east bank of the Nile, in Egypt, about 300 km south of Cairo. Findings include various types of ceramic vessels (bowls, plates, balmers, censers) dated between the sixth and seventh centuries AD. The collection of ceramics, which is now kept at the Istituto Papirologico Vitelli in Florence (Italy) [58], has meant that the residues of the products that people cooked, stored or otherwise used in Roman Egypt can be chemically studied. The results described below relate to the analysis of residues of the dark material in two clay lamps (nos 718 and 809) of the collection. 

Carretero et al. 2006, Droy-Lefaix and Tateo 2006). Likwise, Sudanese villagers along the Nile have traditionally used a local bentonite clay to rid river water of viruses and bacteria (Lund and Nissen 1986, Madsen and Schlundt 1989). For a description of the modern-day uses of clays and clay materials in various industries the reader is referred to the reviews by Murray (2003) and Harvey and Lagaly (2006). 

The test bars of the Nile mud were reddish brown (5YR 5/4) in the Munsell color notation at the 600°C zone of the gradient firing, red (2.5YR 5/6) at 850°C, and darkened with incipient vitrification to weak red (2.5YR 4/3) at 1100°C after a holding period of 30 minutes. The scratch hardness, using Mohs scale, increased from 3.0 to 6.5 for the male (better working clay in the potters terminology), and from 2.3 to 5.0 for the female mud. The Nile mud shrank far more when fired... 

The needed Egyptian data were obtained from as yet unpublished work on Egyptian clays, Nile muds, and ceramics carried out at Brook-haven by Sami Tobia. Since the results compared favorably with published material (9), further Egyptian studies were not carried out. 

Examination of the Egyptian material led to a further discovery. The general Nile pattern, produced by Nile muds and the ceramics made from it, is on first glance very close to that of the Palestinian red field clay. When the plots of three clays and six sherds were matched by the scandium—iron points, cobalt, chromium, and europium also matched exactly. Thus in the Nile samples, concentrations of the five elements are highly mutually correlated. This observation then allowed detection of subtle differences between Palestinian and Egyptian materials. The... 

Below the sediments disrupted by cultivation, a unit (Unit A) was found that was about 120 cm thick and that contained a disorderly mixture (almost an inverse time sequence) of Roman, Pharaonic, and Predynastic sherds. The next 15 cm or so was a clay-rich Nile silt (Unit B) in which there was a normal ceramic sequence with sherds dating from about 300 B.C. to about 2500 B.C. Table I describes the typical core sample. The layers of sediments were compacted and, in some cases, partially hardened by a calcareous cement, but in all cases, the samples could be easily crumbled. 

Vermeesch (15) recorded a series of sediments under the cultivation zone at El-Kab that included the Nekheb lithozone (fine sand and clay), that was assigned an age earlier than the Predynastic period. When sand-sized fractions of Nekheb material from El-Kab were analyzed, it became clear that the Nekheb formation and Unit N at Hierakonpolis were the same Nile sediments. In Figure 8, the correlation of Cr, Th, and Hf in the Nekheb formation is the same as for Unit N. The REE distribution patterns for these two groups of sediments also match (Table V). This approach not only allowed similar Nile sediments to be distinguished (Units B and N) but also allowed us to match deposits from different locations in the area (El-Kab and Nekhen). 

During Pliocene times, the overdeepened Nile Trench was invaded by the sea, which deposited thick beds of montmorillonitic clay interbed-ded with sand, organic rich detritus, and gravel (J-3). Later, during Late Pleistocene and Early Holocene times, the lower Nile Basin was overlain with a series of silt units as sediments were carried from the Upper Nile drainage basin. Some of the overlying silt formations along with the... 

Although the number of samples analyzed is limited, the inescapable conclusion to be drawn from our data is that some of the Nile silt formations can be differentiated on the basis of trace element contents and REE distribution patterns. In addition, we conclude that the Early Predynastic (Amratian) pottery was made from clays found in the immediate vicinity of the kiln. Older shales that are found layered with the much earlier sandstone deposits that were cut by the Great Wadi were also analyzed. The REE patterns as well as the scandium, chromium, and iron concentrations are different enough to suggest that these materials were not used to produce pottery (21), In a previous paper, we discussed the possibility that some of this shale, or the white salt found associated with it (anhydrite-CaSOj, was mixed with the local clay to produce the finer, harder plum red ware (21). This addition could account for the slight difference in the average composition of the sherds from localities 11, 39, and 59 and the Masmas silt. 

In Egypt the dried clay bricks without burning were hnked with Nile slim (2). Such construction was effective in dry climatic zone only, because low moisture durability of these materials. Also the blocks in first stairs Djoser s pyramid were linked with clay (twenty seventh century before Christ) in Sakkara [2]. 

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