Natural Science in Archaeology

10.5 Alum 231
times in Egypt. White and other colored leather sandals are seen in tomb paintings
from the New Kingdom which may have been fabricated by using alum. Alum may
also have been used in combination with honey as an astringent by the Egyptians to
dress wounds (Lucas 1989). Herodotus relates that the Pharaoh Amasis offered 1000
talents for alum to be sent to Delphi (Harris 1961:197). The Ebers Papyrus prescribes
its use as an eye salve. The use of alum for tumors is found in the Berlin Papyrus, and
Pliny and Dioscorides note this particular use. Ancient workings have been found at
the Dakhla and Kharga Oases west of the Nile valley. Greek papyri confirm that alum
was used in the Hellenistic Period when it was extracted under a royal monopoly
(Oxyrhynchus Papyri 17, 2116). Pliny and Dioscorides claim Egyptian alum is superior
to that found elsewhere, and both state that there are several types. Pliny refers
to its use as a mordant for dye and as an ingredient in medicines (N.H. 35, 52, 184).
Alum was produced in large quantities in Roman Egypt. Surface pottery sherds at the
Kharga Oasis indicate that this source continued to be exploited in Roman times.
There is evidence of tawed leather in Assyria, Babylonia, Phoenicia, and ancient
India. There are deposits of alum in Mesopotamia near Kara Hissar on the Lycus
River at Tuz Khurmatli, and Hamairan on the Persian Gulf. Alum was used by the
Assyrians as a styptic (Campbell Thompson 1925), and its characteristic astringency
is noted by Pliny. A Mesopotamian recipe for the use of oil and alum for making
sandal leather has been translated by Thureau-Dangin (1920). It was also used in
Mesopotamia in glass-making. Alumstone (alunite) was used to make seals. The
alum derived from this mineral compound was roasted and boiled in water to be
used in medical prescriptions. Late Assyrian texts mention that alum was imported
from Egypt for use by dyers and leather workers.
In late Preclassical times, Cyprus seems to have produced plumed (plumous)
alum, which may be the compound aluminum sulfate. This substance was imported
to the near East. Alum deposits were also found in Palestine near the Dead Sea and
in Peraea near the town of Machairus. Classical Greeks secured potash alum from
the volcanic island of Melos.
The Romans had access to potash alum from volcanic regions such as the Lipari
Islands and Sicily (Singer et al. II 1954). They also knew of the mineral alunogen
(hydrated aluminum sulfate) and utilized a number of minerals with aluminum
sulfate or compounds similar to alum. Caesar cites the use of tawed leather for sails
(aluta) among the Veneti in Gaul (De Bello Gallico 3, 13).
Tawing with alum was practiced in eighth century Spain. Lucas (1989) mentions
“extensive ancient workings of aluminum sulfate”, and quotes a fragmentary
passage from Arab authors for more recent alum trading, associating the use of
alum as a mordant in dyeing skins. By the thirteenth century, Arab writers discussed
methods of preparing a pure alum from “the alum of Yemen” (native aluminum
sulfate). The manufacture of tawed leather was also widespread in the Middle Ages,
and alum continued to be the common mordant for dyeing fabrics, as evidenced by
textual and pictorial representations (Singer et al. II 1954). In the thirteenth century,
most alum came from the Greek islands and the Near East, especially the region
around Izmir. Prior to the fifteenth century, alum was imported into Europe from a
number of sources but mainly from the Byzantine Empire. After the Turks captured