Jingdezhen
classical porcelain is unlike any other clay. Westerners have described
its properties as like throwing cottage cheese. The first porcelain
of late 10th century Song Dynasty consisted of one ingredient, chinastone
felspar, petunze in the local dialect. The rock was ground into a paste
by water-powered hammer mills, a practice still in use today. The restrictions
of throwing wet powdered stone resulted in the intimate wares of Song
and Yuan dynasties. Kaolin clay, gaolin, was discovered around 500 years
ago during the Ming Dynasty in the mountain village of Gaolin. This
addition of white gaolin clay to the petunze gave a structure to the
porcelain and made possible the throwing of large forms, both as complete
pieces and in the sectional cylinders of the body-height vases.
Since
the Ming period, the composition of the porcelain body has remained
60 per cent chinastone and 40 per cent kaolin. Both materials were traditionally
made into brick shapes and mixed together. Before the invention of the
pugmill, craftsmen would wedge a large mass of clay with their feet
into a circular mound. Now it is pugged and then lightly rolled towards
the body. Containing no ball clays and thus having little plasticity,
classical Jingdezhen porcelain is an adventure to throw. The general
rule is to throw thick walled pieces and, when thoroughly dry, trim
both the inside and outside to desired thickness. As much as half the
body will be trimmed away. The wheel is run on a large and powerful
electric motor with pulleys. An old-fashioned lever that clicks into
notches regulates the speed, much like the old farm tractors. Thick
bats, more than one metre in diameter, are centred on the wheel head
and stay in place by the sheer weight of the clay.

The next step is to get a dozen or more of the 10 kilo
porcelain balls on to the wheel. The growing mound is centred one ball
at a time until a sufficient mass is attained. Initial centring requires
the help of an assistant grasping the hands of the master thrower and
forcing his energies through the master’s hands to centre the
clay. At some studios two assistants steady the master’s hands
for centring and opening. The centred clay is then opened and the bottom
is quickly widened to its desired measure. The walls are raised progressively
and then shaped. An assistant’s hands are used in the throwing
until the final shape is near. The last shaping is completed by the
master alone until the form reaches 1.5 m in diameter. The apparent
simplicity and ease belie a master’s touch with a difficult material.
The rim is carefully measured with a stick. Many shapes are parts of
a two or three piece finished form.
Sections are assembled after the pieces have become bone
dry in the sun and each section has been rough trimmed. A slurry of
pancake batter consistency is made with the trimmings from the specific
pieces to be joined. This is poured on to the rim of the bottom piece
and the top section is lowered and centred. Within 10 seconds the trimmer
begins to shave the assembled form to a final shape. The tools are kept
razor sharp. It takes four men to haul away the porcelain form on a
wooden platform with handles and take it out into the sun to dry. If
it does not crack here it will make it through the firing. Attempting
to trim Jingdezhen porcelain before it is dry is folly because the tools
gouge out chunks of clay. The tools and the process must follow the
nature of the material. A final soaking of the surface with a thick
round brush dipped in water reveals any imperfections such air bubbles
which must be removed.

Cobalt
blue qinghua decoration is frequently brushed on to to the greenware
by skilled painters. A clear glaze is applied with spray gun –
formerly by spray can and strong lungs. All Jingdezhen wares are once-fired
at 1300–1330°C in propane gas kilns – the old coal-fired
kilns are being phased out. Enamels or gold lustres can be added with
an additional firing at 800°C.
Jingdezhen is the home of nine of the 26 Masters of Art and Craft of
China, the highest national accolade. This title is generally reserved
for the decorators. The unsung craftsmen throwers are hidden away in
factories and one stumbles upon them to watch in awe at their tremendous
skill and humbleness. During the events of the Jingdezhen 1000 Years
Celebration of Porcelain taking place in 2004 and 2005, visitors will
be rewarded by a guided tour to the factory studios to learn the secrets
of classical porcelain techniques, including the virtuosity of the master
throwers.