Page 138 - Index Pottery of Dvaravati Period - Professor Emerita Dr.Phasook Indrawooth

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physical sciences will provide information about the manufacture of the pottery

whether or not the clay had been levigated before use, the addition of tempering
materials and changes in the degree of oxidation of some minerals which will help

showing the extent to which the pottery had been fired.

In this work, we are concerned with the analytical and typological study or
potsherds excavated from various archaeological sites of central Thailand in Dvaravati

period (about 600 – 1,000 A.D.) i.e. Chansen, Nakhon Sawan Province, Ban Ku Muang,
Signburi Province, Ban Tha Kae, Lopburi Province, Ban Ku Bua, Rajburi Province, and

ancient Nakhon Pathom, Nakhon Pathom Province.

Prior to the process of examination, all of the potsherds have been washed,
catalogued and assembled as parts of restorable vessels. If the latter is not possible,

they should be grouped according to the vessel area from which they came:
rims, shoulders, body pieces, bases, handles etc. Further step to be done is to examine

the interior and exterior surfaces of sherds and of freshly fractured cross sections

through body walls, by hand lens or a low power binocular microscope, to learn about
the surface straitions and textural variations. Then specimens of sherds are sent for

the identification of their mineral inclusions. In this work only the chemical properties

of Dvaravati pottery are presented.
The analytical study on pottery excavated from Dvaravati sites in central

Thailand has led to conclusion that Dvaravati pottery are unglazed earthenware made
in wheel throwing method (but free hand method is observed among small vessels)

and fired in the open-hearth kiln where the firing atmosphere cannot be controlled.

The unevenness in color of Dvaravati pottery reflects the fluctuations in firing
atmosphere.

The chemical analysis of Dvaravati pottery has pointed to conclusion that the
raw materials used by Dvaravati potters occur locally in the Chao Phraya River Basin

where the red clay or surface clay with a mixture of carbonaceous matters and iron

compounds are found. The red clay when fired in oxidized atmosphere, it will become
red or reddish brown and in reducing atmosphere it will become gray or black. Almost

all Dvaravati specimens have black cores which indicate incomplete oxidation resulting

from one or more conditions, i.e. short firing, low temperature of insufficient oxygen
in the firing atmosphere. An we know that the primary causes of pottery color are

the composition of clay and the atmosphere, temperature and duration of firing.

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