quantitative way, but only through an understanding
of how the materials, the recipe, the firing, and
the potter's understanding are all integral parts of
one relationship.

MAKING A PORCELAIN BODY: THE MATERIALS

The materials generally used by studio potters for
making porcelain are few in number, varying little
from china clay, feldspar, quartz and bentonite.

THE CLAY: For making porcelain which is really white,
English china clays are probably the best in the world.
They are very low in iron and titanium, and also very
low in plasticity. I have used three different china
clays for making porcelain bodies: Standard Porcelain,
Grolleg and Treviscoe. All come from English clays in
St. Austell. At times I have been more partisan to
one than another, and well might be again, but at the
moment I don't think that any is unequivocally superior.
It's the recipe that matters, and how it is used.

Ball clay, tempting to use because of its plasticity,
is better left out unless you are content with white
Stoneware. [ have never seen a translucent ball clay
body. I don't really know why, but I suspect the iron
and titanium content.

Fireclay, I have been told, can be used to make por-
célain, but only in those parts of the world where a
fireclay low in iron and titanium is available. I do
not know of one in England, but in America there are
clays called flint fireclay which might satisfy these
conditions and combine with them a higher degree of
plasticity than that of china clay.

THE FELDSPAR: The body-fluxes used in porcelain are
generally added in the form of feldspar (and/or the
related alumino-silicates Cornish stone, nepheline
syenite, petalite). The reason is simple. The fluxes
they contain are predominatly soda, potassium and
lithium (see note below) and these fluxes, the alkaline
metals, have a long, slow, steady action in their
melting. The other forms of these fluxes, such as soda
ash and pearl ash are soluble materials and difficult

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