Test

Question 1

What is clay?

Answer 1

Hydrous silicates of aluminum.

Question 2

What is the chemical makeup of clay?

Answer 2

Al2O3 + 2SiO2 + 2H2O

Question 3

Where does clay come from?

Answer 3

Weathered product of igneous rocks. On or below earths surface.

Question 4

2 major types of clay?

Answer 4

Primary (residual clay: can be mined from the parent rock) and Secondary (sedimentary: clays that have been deposited in their present location by water, ice, and other weathering).

Question 5

3 major qualities of clay?

Answer 5

Plasticity: must be easily shaped and hold shape well.
Porosity: must be open in structure to allow the water of plasticity to escape readily on drying.
Vitrification: must become dense, hard, strong, at a temperature suited to the production requirements.

Question 6

Plastic

Answer 6

Very moist, moldable.

Question 7

Leather hard

Answer 7

Moves but still holds shape, lost a lot of moisture but still not totally dry, carving done at this stage.

Question 8

Green ware

Answer 8

Bone dry, no physical H2O, unfired.

Question 9

Bisque

Answer 9

Unglazed, fired once to remove all moisture from the clay body.

Question 10

Glazed

Answer 10

Glaze is powdery/dry before second firing.

Question 11

Glaze fired

Answer 11

Glaze materials melt and form a vitreous coating on the clay surface.

Question 12

Pinch

Answer 12

Hand building technique where clay is “pinched” by hands

Question 13

Coil

Answer 13

Clay rolled into coils for building.

Question 14

Slab

Answer 14

A thin slice/plate of clay. Made by using a roller.

Question 15

Scoring and slipping

Answer 15

Scratching clay surfaces then adding slip (water and clay). Done to attach two pieces of clay to assure they don’t come apart.

Question 16

What is decorative slip made of?

Answer 16

Clay and a colorant.

Question 17

How is decorative clay colored?

Answer 17

With oxide or colorant.

Question 18

What is joining slip made of?

Answer 18

Water and clay from the clay body that is being used.

Question 19

Mishima

Answer 19

A design is carved into the clay body, slip is painted on the surface of the clay, then the outer layer is scratched off, leaving an indented colored design.

Question 20

Scrafitto

Answer 20

Slip is applied to the surface the clay body, then the slip is carved away to make a design.

Question 21

Slip trailing

Answer 21

A bottle with a smaller opening is used to draw a design.

Question 22

Painting

Answer 22

Slip is painted on with a brush

Question 23

Stenciling

Answer 23

A stencil or paper is laid on the clay body, the slip is put over that then the stencil is removed.

Question 24

What is a glaze?

Answer 24

A layer or coating of a vitreous substance, which has been fire to fuse to a ceramic object to color, decorate, strengthen, or waterproof it.

Question 25

3 main elements of glaze?

Answer 25

Glass: high melting temperature and is fragile.
Fluxes: promotes the melting point of the glaze; affect colors, textures, crazing, etc.).
Refractories: resist melting, will not melt alone; contribute to the durability of the glaze, mainly hardness and insolubility.

Question 26

Differences in:
Transparent vs. Opaque
Glassy vs. Matte

Answer 26

T vs. O: transparent has more glass, and is see through

G vs. M: glassy has a shiny finish while matte is looks unpolished.

Question 27

What are the two main sources of fuel for our kilns?

Answer 27

Gas and electric (gas provides more dramatic coloring)

Question 28

Difference between oxidation and reduction atmosphere?

Answer 28

Electric kilns use oxidation, while gas are reduction. Oxygen supply is restricted in reduction.

Question 29

What is a Raku firing?

Answer 29

Fast firing method, originated in Japan, starts at room temp then goes to cone 06.

Question 30

What types of clay do we use?

Answer 30

Earthenware: fires below cone 2, red/brown in color
Stoneware: has multiple firing temperatues