Mud; moist, sticky dirt.
In ceramics, clay is fine-
grained,firm earthy material that is
plastic when wet, brittle when dry,
and very hard when heated.
The most common types of
ceramic clays are:
Earthenware is a low-fire clay that
is porous and not waterproof.
It can be made waterproof by
You will use earthenware clay to
roll out a slab and create a ceramic
Clay Slab Plan
First plan on newsprint.
What will be your theme…Nature or
What shape expresses your theme?
What decoration helps express the
Does the container need additions…
“feet”, handles, top, lid, pictures?
Clay Slab Plan
Roll out a slab of clay
Cut the sides, then bottom & top
REMEMBER when measuring,
clay has thickness.
Decide how the sides will overlap and how
thick the slabs will be before figuring the
size of the bottom of the slab piece.
When the slabs are rolled out, and
they are cut to size, they should be
allowed to dry to the leather-hard
stage before assembling .
This is the first stage of drying. There
is still moisture in the clay, but it is
just dry enough to hold its shape
and not “slump” This stage of
drying is called leather-hard.
When the slabs are leather hard,
they can be assembled by
scoring (scratching) and
slipping the edges to be joined.
What is scoring and slipping????
Score the clay that is to be joined
the pieces of
clay to be
Add clay slip to the scored pieces
to join them together.
Clay slip is a fine,
liquid form of clay
used to cement
together parts that
have been formed
finely ground clay
with water makes
The scratched and
slipped edges should
be pressed firmly
together and the joints
blended with a finger
tip or a small tool.
Square corners should be given
additional support on the
inside. Make a coil the size of
an earthworm, lay it carefully
in the inside corner and
smooth it into each side of the
When finished, your greenware
container needs to be thoroughly
dry before it can be fired.
This stage of drying is called
Greenware - Bisque
Unfired clay is Fired clay is
Green ware Bisque ware
Clay is hardened by heating it to a
high temperature, thus fusing the
clay particles. Temperature in kilns
can reach 2500 degrees.
The bisque clay container is now
ready to be glazed.
Glaze is a coating of material
applied to ceramics that forms a
glass-like surface when fired a