Creating Porcelain Dinnerware With Slump Molds and Hump Molds

Porcelain pottery is made from kaolin, a whiteroll the clay out, but slab rollers make for a more
clay which melts at extremely high temperatureseven slab. Roll until the slab is about 1/4" thick.
and feldspar, which melts into a glassy cementSpray a lubricant over the surface of the hump
and binds the ceramic together. Porcelain isor slump mold, and lay the slab of clay over the
characterized by a hard, white, translucencetop. Press the slab into the mold with a damp
substance. Originally manufactured with humpsponge and trim off the excess clay around the
molds during the T'ang period (618 - 906 C.E.), theedge of the mold, cutting vertically with a knife.
technique was refined during the Yuan periodAllow the plate or bowl to dry thoroughly. Then
(1280 - 1368 C.E.) by the inclusion of cobalt toremove the piece from the mold and apply a
produce a blue and white ware. The Ming periodpaste of kaolin clay to fill small holes and even out
(1368 - 1644) saw the inclusion of other colors asany blemishes in the surface. Smooth the
well. Porcelain pottery was introduced into Europesurfaces with a rasp and fine sandpaper; and
by Marco Polo at the end of the thirteenthfinish the smoothing-out process with a damp
century. Grand Duke Francesco de' Medici ofsponge.
Florence was so taken by this pottery that heBisque-fire the pieces at 980 degrees Celsius. This
commissioned his palace artisans to experimentlow-temperature firing is the key in producing the
with different clay and glaze mixtures, kilns, andcharacteristic porosity of porcelain, and it prepares
styles to create thousands of porcelainthe surface left by the hump or slump molds for
dinnerware objects. Porcelain dinnerware was firstglazing. The bisque-fired pieces should be
produced commercially in Europe in 1710 inquick-dipped into a pegmatite and quartz glaze
Meissen, Germany.which is mixed just prior to application. This glaze
In order to recreate porcelain dinnerware of youris clear and seals the surface, and requires some
own, you will need kaolin clay, WD-40, modelingskill in holding the plate properly while dipping in
tools, water, glazes, and a kiln. You will also need aorder to assure an even coat. Allow the piece to
slump or hump mold. The difference is that humpdry completely for at least 48 hours. You can
molds have a convex surface and slump moldslightly touch up the surface with tools to remove
have a concave surface. These can be purchasedsmudges, drips, uneven patches, and other flaws.
from art supply houses in a variety of shapes andThe piece should be fired one more time at 1,380
sizes. To begin with, mix the kaolin clay withdegrees Celsius in order to obtain the
water according to the instructions on thecharacteristic porcelain finish.
package. You can use a slab roller or rolling pin to