Ceramic Terms To Know
Ceramics:
Objects made from earthly materials with the aid of heat.
Hand building Terms
Hand building:
This term refers to the one of several techniques of building pots using
only the hands and simple tools rather than the potter’s wheel. The term
used for creating pottery, using the potter’s wheel is “throwing”
Pinch Pot:
“Pinch” in ceramics is a method of shaping clay by inserting the thumb of
the one hand into the clay and lightly pinching with the thumb and fingers
while slowly rotating the ball in the palm of the other hand. Pots made in
this manner are called “pinch pots”
Coil:
This is the technique of building ceramic forms by rolling out coils, or
ropes, of clay and joining them together with the fingers or a tool.
Molding:
In this technique, flats slabs of clay are pressed into molds in order to
create various shapes and forms.
Reclaim:
Wet, sloppy, muddy looking clay in buckets or plaster slab. Consistency
is very wet, chunky, and muddy. Great to use as Slip.
Slip:
Slip is liquid clay. The easiest way to make slip is to gradually sift or spoon
dry, powder clay into a small cup of water. Stir well as you add because it
will tend to thicken up after it sits for a minute or two. You want it to be
about the consistency of thick cream.
Plaster Slab:
Large white blocks where failed thrown pots are placed. Used in the
reclaiming process before clay is placed into the Pugmill.
Score and Slip or
Scratch and Slip:
Score and slip refers to a method of joining to pieces of clay together.
First, score the clay; this means that you make scratches in the surfaces
that will be sticking together. Then you slip it; that is you wet the surface
with some slip, using it like glue. Next, you press the two pieces
together. If you don’t score and slip your pieces they will likely pop apart
when they are fired.
Blending or
Smoothing:
Smoothing clay that has been added to your project with the score and slip
method.
Stages of Dryness:
When speaking of clay, we refer to three basic stages of dryness: Wet,
Leather hard and Bone dry.
Wet: The consistency of clay right as it is taking from the bag. This clay
is easily manipulated, used for making projects.
Ceramic Terms To Know
Leather Hard: The clay can no longer be moved or bend, usually will
break if dropped, might have some discoloration, especially on the tips and
ends of projects. The clay will feel cold to the touch.
Bone Dry: The consistency is chalky and dusty. There shouldn’t be any
discoloration but rather a pale white color. Upon touch the clay should
not feel cold.
Pugmill:
Machine used to reclaim used clay.
Grog:
Crushed or ground particles of fired clay added to clay to help drying and
reduce shrinkage and warping.
Decorative Techniques and Terms
Sgraffito:
Sgraffito is a decorating technique developed centuries ago. In
its simplest embodiment, leather-hard clay is coated with an
engobe or slip of contrasting color and then a pattern or
picture is added by carving through or scraping off the slip to
reveal the clay underneath.
Wax Resist:
In this decorative technique, patterns or designs are created by brushing a
wax medium over an area of clay, slip or glaze to resist the final glaze
application when the wax is dry.
Stamping:
This is the technique of pressing forms into the clay to get decorative
effects.
Delamination:
Unfired clay slabs expanding away from each other by adding to much
water or under glaze or glaze.
Calibers:
Tool used to measure the opening of a form.
Wire Tool:
Tool used to cut clay from the potter’s wheel.
Firing Processes and Associated Terms
Firing:
This is the process of heating the pottery to a specific temperature in order
to bring about a particular change in the clay or the surface.
Kiln:
The machine used to fire pottery, like a big oven, reaching temperatures
up to 2400degrees F. We fire to 1926 degrees F.
Bisque:
The term bisque refers to ceramic ware that has been fired once without
glaze.
Greenware:
This refers to ceramic ware that has not been fired.
Ceramic Terms To Know
Glaze:
A glass-like surface coating for ceramics that is used to decorate and seal
the pores of the fired clay. Changes color while it is being fired.
Under Glaze:
Applied prior to glazing, used for decorations and details. Does not
change color. After the firing underglaze is matte and still porous. Clear
glaze is applied over underglaze to give the finish a glossy finish.
Reduction:
A kiln firing in which there is a insufficient oxygen to consume the free
carbon emanating from the heated glaze and clay, resulting in the
formation of carbon monoxide. Oxygen-starved carbon monoxide pulls
oxygen from the clay body and glaze, forming color changes in the
coloring oxides.
Oxidation:
A kiln with a full supply of oxygen (opposite to a reduction firing) Electric
kilns are this type.
Part of a Vase
Mouth:
The opening at the top of the Vase.
Neck:
The (usually) narrower part that leads from the body of the vase to the
mouth
Body:
This is the main part of the vase. It is usually the largest part.
Foot:
This is the part of the Vase that meets the floor.
Throwing Terms
Bat:
Round disc placed on the wheel head that is used for throwing.
Throwing:
The action of making pots on a quickly rotating wheel
Centering:
The act of forcing a lump of clay by hand into a symmetrical form.
Cone up:
A pyramidal shape that occurs when you compress the clay on the potter’s
wheel
Opening:
Slowly pulling the clay out to form a “well” in the center of the clay
Pulling:
Lifting the sides of the clay to create a wall
Collaring:
Using 2 hands and gently squeeze the clay from the bottom to the top of
the pot. Used to help bring the pot back on center.
Lip/Rim:
The top edge of the Pot.
Dropping the Center:
Pushing the center of the clay down to form an opening.