No. 237 Maritime Archaeology in the People's Republic of China ...

scarcity around Jindezhen, forcing porcelain manufacturers to
go 300 miles for wood by the 18th century (Rice, 1987:163).
Coal mining was well developed in the Song Dynasty, though
mainly in the northern part of China. Coal had the advantage
of rapid ignition and a high lasting temperature, properties that
allowed the clay, glaze and pigments to fully react chemically
and resulted in better quality. Both fuels are used in Fujian
Province today.
Fireclay saggars (or saggers) were built as protective
containers for firing. These were boxes of refactory clay in
which one or more ceramic items were placed during firing,
to shelter the pieces from direct flames or ash. In reduction
firing, the saggar should be airtight and in oxidising firing air
should be allowed to enter. These saggars absorbed substantial
amounts of heat and different stacking methods were employed
for ceramics inside according to the type of ceramic. The wares
were either stacked upside down on unfired stepped rings with
their mouth-rims unglazed to avoid fusing or in a saggar that
required only the foot rim to be unglazed. Stacking of the
bowls in the kiln can be established from the rims and unglazed
portions of the bowls excavated from Bai Jiao 1. The black
glazed bowl was fired in separate saggar firing moulds (Figure
39), while the celadon were stacked one bowl inside the other
(Figure 40). For glost firings the glazed wares may have been
carefully separated by small tripods called stilts or props so
that they did not touch each other and mare the glaze.
Stone weight (?)
One stone weight was a recovered from Bai Jiao 1 and
another was collected during a survey for new wrecks site.
Identification of the use of these stone objects could not be
confirmed, although net weights or perhaps sounding weights
are a possible interpretation (Figure 41).
Concretions
Several small concretions were removed from the site, some
embedded with ceramic material. Initial inspection what ferrous
material formed the conglomerate although x-ray analysis will
be undertaken in China.
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