Clay forms over vast spans of time from the weathering and erosion of rocks containing feldspar minerals. During weathering, hydrolysis alters the feldspar content to form clay minerals like kaolin and bentonite, which make clay plastic and moldable. Clay can exist in various states, from greenware before firing to bisqueware after the initial firing and glazeware after final firing with glaze.

1. © SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016
CLAY PROCESSCLAY PROCESS

2. Clay is a soft, loose, earthy material with a fine grain.
It forms as a result of weathering and erosion of rocks
containing the mineral group feldspar over vast spans of
time.
During weathering, the felspar content is altered by
hydrolysis to form clay minerals such as kaolin and
bentonite. These are the elements that make clay
plastic and moldable.
WHERE DOES CLAY COME FROM?
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

3. © SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016
Hydrolysis
● Hydrolysis is the chemical reaction (cation exchange) of a compound with
acidic water
Example: Feldspar is converted to the clay mineral kaolinite

4. WHERE DOES CLAY
COME FROM?
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

5. STATES OF CLAY
GREENWARE
BISQUEWARE
GLAZEWARE
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

6. GREENWARE
Clay is known as “green” before its
first firing.
Stages of greenware can be
categorized by their respective level of
dryness/wetness.
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

7. GREENWARE
Slip
watery / paste
used for “glue”
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

8. © SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016
SCORE AND SLIP IS
THE METHOD OF
ATTACHING CLAY
TO CLAY.

9. GREENWARE
PLASTIC
mushy → impressionable
This is a good stage to mold and sculpt.
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

10. GREENWARE
LEATHER HARD
dried out some, starts to harden to the point of being less
impressionable
This is a good stage for trimming, cutting, carving, and
attaching parts.
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

11. GREENWARE
BONE DRY
all physical water has dried
At this stage you can still scrape and scratch.
Ready for the first firing
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

12. PUT THEM IN
THE KILN
BISQUE FIRE
1st firing
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

13. BISQUEWARE
Glaze + Other Surface
Designs
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

14. PUT IN KILN
GLAZE FIRE
final firing
Fire at 10.
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016

15. © SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT
BEFORE AFTER
GLAZE FIRING
MOST TIMES UNFIRED RAW GLAZE IS NOT INDICATIVE OF THE FINAL FIRED GLAZE COLOR.

16. GLAZEWARE
FINISHED PRODUCT
© SCOTT SHAKESPEARE | LA SIERRA UNIVERSITY ART+DESIGN DEPARTMENT | 2016