Greenwich House Pottery

Greenwich House Pottery
16 Jones Street, New York, New York 10014
p: 212-242-4106 f: 212-645-5486 e: [email protected]
Visit us online: greenwichhousepottery.org

facebook.com/greenwichhousepottery
twitter.com/ghpottery
Est. 1909

YSchool Year 2010-2011
NLGreenwich House Pottery (GHP) is one of the oldest non-profits in the country

dedicated solely to the inquiry and advancement of the ceramic arts. GHP has been

Oeducating and introducing New Yorkers to clay since 1909. Over the past 100-years it
Ehas become an internationally recognized center for ceramics - offering a diverse

program of classes for adults and children – Solo, Group and Juried Exhibitions –

SArtist-in-Residence program – Lecture Series – Summer Masters Series workshops -
Uand Community Outreach, all of which serve newcomers, amateurs, and professional
Lartists alike.
AWith one of the largest ceramics faculty of any ceramic educational facility, GHP has
Nsomething for everyone. Many important figures have taught, lectured, exhibited, or
IOtaken classes within these walls such as Rudy Autio, Ruth Duckworth, Shoji Hamada,

Tony Hepburn, Margaret Isreal, Jun Kaneko, Bernard Leach, David Leach, John

E TLeach, Warren MacKenzie, Louise Nevelson, Don Reitz, Byron Temple, Robert
L ATurner, and Peter Voulkos, to name a few. In 2009, New York City Mayor Michael
SA CBloomberg awarded GHP a Mayoral Proclamation and declared September 10th, 2009
E U“Greenwich House Pottery Day”.
R DExtending our educational mission, GHP, maintains an ongoing exhibition series. The
EJane Hartsook Gallery and The Pottery Shop at GHP are committed to supporting
R both emerging and established ceramic artists, and to the educational mission of
Ymaking, exhibiting, and learning from contemporary ceramics.
FO ER About Greenwich House, Inc.
T T Greenwich House Pottery is a program of Greenwich House Inc., a settlement house
O T founded in 1902 by Mary Kingsbury Simkhovitch. Located at 27 Barrow Street,

Greenwich House offers a wide array of programs designed to enrich the lives of New

N O Yorkers, including the Barrow Street Nursery School, Music School (46 Barrow
P Street), Substance Abuse, Children’s Safety Project, Judith C. White Senior Center,

Senior Health & Consultation, and health care and services for people living with

E HIV/AIDS.
US Our programming is made possible by the generosity of foundations, corporate
O sponsorship, and through individual charitable gifts by people like you.
H H Welcome to GHP, and thank you for your continued support.
GREENWIC Cover: Woodblock Print by Peter Gourfain, 2010 (Altered)

Back: First GHP Brochure 1948-1949 Jane Hartsook, 1948

12

OUR FACILITIES CLAY BODY RECIPES
We offer 35 Adult classes, a Children’s class at 27 Barrow Street, 2 Parent & Child
classes, a homeschool class, Summer Master Classes, and Summer Camp for children T-1 STONEWARE SCULPTURE BODY

and teens. Day and evening classes are scheduled Monday through Saturday. Our Firing Range: Δ06-12, Oxidation or Reduction
studios are equipped with 2 handbuilding classrooms, 2 throwing classrooms, 28
Shrinkage: Green = 7%, Δ06 = 8%, Δ04=8%, Δ2=11%, Δ10=13%

potters wheels, 2 up-draft gas kilns, 4 Skutt computerized electric kilns, a slab roller, 2 Porosity: Δ06 =10.9%, Δ04=10.3%, Δ2=4.9%, Δ10=1.3%

Color/texture: Orange-tan with iron brown specks dense with good green strength
Soldner clay mixers, one Peter Pug mill, 2 clay extruders, and a spray booth. We offer
Ingredients: Measurements are in POUNDS
5 clay bodies: white stoneware, throwing stoneware, sculpture stoneware, red
Hawthorne Bond Fire clay 200
Yearthenware, and we sell grolleg porcelain for $18 per 25-pounds. We have a large
Lselection of glazes (23 high temperature and 18 low temperature), slips and washes, Thomas Ball clay 28
Nand offer low, mid, and high temperature firing (cone 04, cone 2, & cone 10).
OCLAY BODIES Lizella 20
EGHP clay bodies have been tested and in use at GHP for decades. The recipes herein
Bentonite 11
were not developed by members of the Pottery but rather were introduced through
Fine grog 70
Scontact with their inventors; therefore, we cannot take credit for them. All clay bodies
Uare suitable for Handbuilding and Throwing. The first 3 clay bodies can be used for Medium grog 30
Lboth high-fire and low-fire and used in reduction or oxidation atmospheres, although
Aresults vary according to atmospheric conditions and the temperature reached within STONEWARE THROWING BODY (JEFF OESTREICH)

the kiln. The DiCarlo Earthenware is a low-fire clay body and is not formulated for Firing Range: Δ06-12, Oxidation or Reduction

Ntemperatures above Δ04 (Cone) firings (though we use it to good effect in our Δ2 Shrinkage: Green = 6%, Δ06 =7%, Δ04=8%, Δ2=12%, Δ10=15%
IOfirings).
LE THigh-fire indicates the clay bodies are formulated to vitrify at or around Δ10. Porosity: Δ06 =13.5%, Δ04=12.7%, Δ2=4.3%, Δ10=.4%
ATypically, though not always, high temperature firings occur within a reduction
SA Catmosphere. Low-fire indicates the clay bodies are formulated to mature at or around Color/texture: Tan-Brown, speckled in reduction smooth clay
E UΔ04. Low temperature clay and firings are likely fired in an oxidation or neutral
Ingredients: Measurements are in POUNDS
atmosphere.
Hawthorne Bond Fire clay 200
R EDOur clays are shipped premixed dry (except our grolleg porcelain which comes
R Ypremixed wet) from Amherst Potters Supply in Hadley, Massachusetts and can be OM-4 Ball Clay 50
Opurchased directly from them. On the web: amherstpotters.com phone: 413-586-4507
F ERSHRINKAGE TEST G-200 Feldspar 30
T TMake eight test bars of each clay, two bars for each firing temperature for better
O Taccuracy. Make the test bars 5” L x 2” W x ½” thick and mark a 10cm line with short Fine grog 30
N Operpendicular lines across the ends of the line. To calculate the shrinkage, measure
Red Iron Oxide 6
each clay bar from wet to dry and from dry to Δ06, Δ04, Δ2, Δ10.
WHITE STONEWARE (GREG PITTS)
E PWet to dry: Line wet – Line dry X 100 = % shrinkage
SLine wet Firing Range: Δ06-12, Oxidation or Reduction

UDry to Fired: line dry – line fired X 100 = % shrinkage Shrinkage: Green = 6%, Δ06 =6%, Δ04=6%, Δ2=10%, Δ10=13%
OLine dry
Porosity: Δ06 =14.2%, Δ04=13.1%, Δ2=6.7%, Δ10=.1%
HWet to dry % + Dry to fired% = % total shrinkage
ICHOn average: Earthenware shrinks about 10% Color/texture: White to grey in reduction smooth and plastic

Stoneware shrinks about 12 – 15% Ingredients: Measurements are in POUNDS
Porcelain shrinks about 15 – 17%
Foundry Hill Cream 40
NWABSORPTION TEST
EUsing the fired clay bars from the shrinkage test, weigh each bar dry. Boil the bars in G-200 feldspar 40
Ewater for an hour, remove each separately, blot it and reweigh:
Flint 325 40
RFired weight wet – fired weight dry X 100 = % of absorption
GFired weight dry Tile #6 40

XX Saggar 30

Pyropholite 10

Bentonite 4

EARTHENWARE (DICARLO)

Firing Range: Δ06-2, Oxidation or Neutral

Shrinkage: Green = 6%, Δ06 =6%, Δ04=9%, Δ2=14%, Δ10=10%

Porosity: Δ06 =9.6%, Δ04=6.9%, Δ2=0.3%, Δ10=0.3%

Color/texture: Red, smooth

Ingredients: Measurements are in POUNDS

Redart 130

Goldart 30

Hawthorne Bond Fire clay 20

Talc 20

Fine Grog 2

PORCELAIN (grolleg)

Firing Range: Δ06-10, Oxidation or Reduction

Shrinkage: Green =4%, Δ06 =5%, Δ04=5%, Δ2=8%, Δ10=14%

Porosity: Δ06 =15.1%, Δ04=15%, Δ2=10.2%, Δ10=0.4%

Color/texture: White, smooth

Ingredients: Not Available

34

ORTON STANDARD CONES AND TEMPERATURES: See page 28 Δ 10 High-fire GLAZES 10,000 grams fill a 5-gallon bucket

High Temperature Δ10 (2377°F)

Mid-range Temperature Δ2 (2124°F) ADAM WELCH’S AVERAGED SHINO (AKA NEW SPOTTED SHINO)
Low Temperature Δ04 (1958°F) Color: Semi-transparent rust red to white with carbon-trapping, dry red when thin.
Bisque Δ06 (1823°F)
Ingredients: Measurements in GRAMS

GLAZES YLike our clay body recipes our glaze recipes come from many sources. The Δ10 andNepheline Syenite3800
LΔ04 glazes at GHP are food safe unless otherwise noted.* This means our glazes areSpodumene1700
Nchemically stable and contain no lead, barium or other toxic material. Whether or notOM 4 Ball Clay1100

a glaze is “food safe” is determined by a number of factors: glaze and ceramicEPK (or Georgia)1000
Kona F4 Soda Spar 1000
Omaturity, glaze-melt, and solubility or stability of fired glaze materials. Our “non-food-Custer Feldspar400
Esafe” glazes are so designated because they are unstable in the fired state and mayRed Art200
Sleach metal oxides into foods, especially acid foods that come into contact with them.
Soda Ash 800
Most of our matte Δ04 glazes are not food safe for this reason, because their matteness
BYRD MATTE
Uis achieved essentially by underfiring, which leaves them unstable.
ALFor a surface to be food safe it must be properly sealed (i.e. clay and glaze haveColor: Opaque matte spotted brown to tan, glossy & blue grey on whiteware

bonded properly and fired to maturity). High-fire clays that have not been fired toIngredients: Measurements in GRAMS

Nmaturity (i.e. Δ6-10) have not had sufficient temperatures to vitrify the clay and bondNepheline Syenite6500
IOglaze to ceramic. Low-fire glazes on high-fire bodies will tend to craze and peel off,
Ebecause their thermal expansion is not suited to the high-fire clay. Food and liquid canDolomite2100
L Tpenetrate the glaze surface. For this reason we consider our low-fire glazes food-safe
AONLY when applied to the low-fire earthenware. Zircopax 900
ESA UC*To be certain of the safety of a glaze have your pottery tested by the Brandywine
OM 4 Ball Clay 500
Science Center. phone: 610-444-9850 web: www.bsclab.com/bsclab_pottery.htm
Bentonite 300
R EDNOTES ABOUT GLAZE APPLICATION PROCESSES
R YAll glazes are affected by glaze application including but not limited to, the thicknessManganese Dioxide200
Oof application, thoroughness of mix, specific gravity (relative density), thickness of the
F Rbisqueware, peak temperature achieved, the surrounding ware and firing atmosphere.Cobalt Carbonate50
ETips:
CHARLIE D BLACK
T T1. Bisque the object
O T2. Quickly rinse under running water, let dry completelyColor: Opaque semi-gloss black, breaks bluish-black over whiteware
N O3. Stir the glaze thoroughly be sure to stir the bottom and sides of bucket
Ingredients: Measurements in GRAMS
4. If using wax or latex resist allow to dry completely before glazing
Nepheline Syenite 2000
P5. Use dipping tongs if necessary and shake remaining glaze off immediately
Ewipe the foot and the lid/gallery Kona F-4 Feldspar 2000

S6. Know the glaze and your desired application (this takes experimentation)Silica 2000

7. If the glaze begins to crack and peel when drying, rub cracks with a dampDolomite1500

Ufinger to hinder further cracking and encourage adhesionTalc 1300
HOMIXING GLAZES
OM 4 Ball Clay 1000
Equipment:
Whiting 200
H1. A triple beam gram scale for measuring.
IC2. 5-gallon bucket - A 10,000-gram batch of glaze will fit in a 5-gallon bucket.Cobalt Oxide500

3. Jiffy mixer and drill. Mason Stain 6600 300 (Black)
4. Sieve - A 60-mesh or an 80-mesh sieve.
Manganese Dioxide 300
W5. Dust mask.
NProcedure: Bentonite 175

E1. Calculate the quantity of glaze desired. Epson Salts 200 (Dissolve in hot water)
E2. Measure the materials using scale; add to an appropriately sized container.

3. Dry mix the measured materials in the container avoiding raising dust.

R4. Wet mix by adding about 2/3 by volume.
G5. Sieve the glaze through a 60-mesh or 80-mesh sieve at least 2 times to
CHINESE WHITE (CRACKLE) (NOT STOCK GLAZE)

Color: Opaque glossy toilet white

Ingredients: Measurements in GRAMS

Custer Feldspar 8300

Zircopax 1000

Whiting 900

Silica 800

remove lumps and evenly distribute materials.

56

CHUN BLUE ***GOATS MILK (No Longer In Use)

Color: Opaque gloss orange rust to mottled baby-blue with some violet on whiteware Color: Matte rosy white to mottled tan

Ingredients: Measurements in GRAMS Ingredients: Measurements in GRAMS

Kona F-4 Feldspar 4556 Custer Feldspar 3193
Silica 2944
Gerstley Borate 952 Dolomite 2317
Dolomite 952 EPK 2140
Whiting 281 Spodumene 2140
Zinc Oxide 184
130 Whiting 210
YEPK 100 Macaloid 100
LBentonite 82
NCopper Carbonate 433
ORutile 281

Tin Oxide
***HAMADA GREEN (No Longer In Use)

Color: Matte mottled green with blacks
SECHUN RED
Ingredients: Measurements in GRAMS

G-200 Feldspar 5860

Barium Carbonate 2370
UIngredients: Measurements in GRAMS
Color: Opaque glossy mottled red to pink-grey when thin on stoneware Whiting 990
LCuster Feldspar
OM4 Ball Clay 790
AGerstley Borate
4230 Copper Carbonate 300

Red Iron Oxide 290
NDolomiteSilica 2680
880 Rutile 230
IOStrontium Carbonate
880 Tin Oxide 90
E TWhiting
400 HIGH ALUMINA MATTE

L AEPK 230
Tin Oxide 260 Color: Matte speckled tan to brown, off-white, and hints of lavender on whiteware

260
AZinc Oxide
S CCopper Carbonate
Ingredients: Measurements in GRAMS

180 Custer Feldspar 4890
E UDARK CELADON
50 EPK 2510
R DColor: Transparent glossy olive green, darker green on stoneware
Dolomite 2240
EIngredients: Measurements in GRAMS
RKona F-4 Feldspar Whiting 350

YSilica Epsom Salts 200 (Dissolve in hot water)

FO RWhiting 4400 MALCOLM’S ULTRA CARBONTRAP SHINO (NOT STOCK GLAZE)

2800 Color: White to Black lots of Carbontrapping (Works best on porcelain)
EEPK 1000
1800 Ingredients: Measurements in GRAMS
T TBarnard Clay
O TDON REITZ GREEN 1200 Nepheline Syenite 4500

N OColor: Opaque matte green to black when thin EPK 2000

PIngredients: Measurements in GRAMS Ball Clay (OM4) 1520

Kona F4 Feldspar 1080

EEPK 707 Soda Ash 1900

Nepheline Syenite 7067 Red Art (optional) 660
SPetalite
UGerstley Borate 1519 ***MAMO GREEN (No Longer In Use)

Whiting 507 Color: Matte rusty brown to pale rosy grey
OCobalt Carbonate
202 Ingredients: Measurements in GRAMS
HRutile
101 G-200 Feldspar 4850

101 Grolleg 2080
H***EMILY’S PURPLE (No Longer in Use)
ICIngredients: Measurements in GRAMS Dolomite 1880

Tin Oxide 790

Color: Opaque semi-gloss creamy purple Whiting 400

WSilica Black Copper Oxide 150

Custer Feldspar 4100
NTalc 1500 NELSON’S CELADON
EDolomite 2000
Color: Transparent glossy light green to icy-green on porcelain

EOM4 Ball Clay 1200 Ingredients: Measurements in GRAMS
Gerstley Borate
Kona F-4 Feldspar 4400
RTin Oxide 700
Silica 2800
GBentonite 500
Whiting 1800
200

Cobalt Oxide 200 EPK 1000
100
Red Iron Oxide 100

Bentonite 100

78

OESTREICH TENMOKU PFARR PINK (NOT STOCK GLAZE)

Color: Opaque glossy black. Breaks brown on whiteware, persimmon on stoneware Color: Opaque satin pepto pink

Ingredients: Measurements in GRAMS Ingredients: Measurements in GRAMS

Custer Feldspar 4838 G-200 Feldspar 4000

Whiting 1164 Silica 3000

EPK 537 EPK 1000

2014 Dolomite 700

224 Strontium Carbonate 600
224 Whiting 310
300 Red Iron Oxide 150
805 Cobalt Carbonate 25

Mason Stain 6020 783 (Pink)
Silica
Zinc Oxide

YBarium Carbonate
LBentonite
NRed Iron Oxide
OOLD YELLOW
EColor: Opaque satin bright buttery yellow to ochre, deeper yellow on stoneware
SNepheline Syenite
SCHERZER (PETE) RED

Color: Opaque satin matte brick red to golden ochre metallic black where thin or thick
UDolomite
Ingredients: Measurements in GRAMS Ingredients: Measurements in GRAMS

6390
LZircopax Grolleg 3700
2110
AOM 4 Ball Clay Silica 1900
1600
Pearl Ash 1100
NBentonite 430
Custer Feldspar 700
Red Iron Oxide 100
IOEpson Salt Whiting 2600
300
E T***ORANGE SATIN MATTE (No longer in use)
200 (Dissolve in hot water) Red Iron Oxide 1000
L AColor: Semi-gloss to satin rusty brown to orange to buttery yellow
Bone Ash 300

SA CIngredients: Measurements in GRAMS
RUTILE GOLD MATTE

Color: Opaque satin matte yellow gold with blues on whiteware, runny if thick
E UCuster Feldspar
Ingredients: Measurements in GRAMS
R DWhiting 4970
Custer Feldspar 4900
EPK 2360
ETalc 380 OM 4 Ball Clay 2500
2010
RBone Ash Dolomite 2250
YRed Iron Oxide
FO RRutile 280 Whiting 350

240 Rutile 800

T TEORIBE 240 ***SPOTTED SHINO (No longer in use)

O TColor: Semi-gloss iridescent darkish green Color: Opaque glossy coppery luster to gold iridescence

Ingredients: Measurements in GRAMS

N OCuster Feldspar Nepheline Syenite 4000

PSilica Spodumene 3000
Ingredients: Measurements in GRAMS
OM 4 Ball Clay 1700
3090
EEPK Soda Ash 800 (Dissolve in hot water)
2530
STalc 780 EPK 500
Whiting 2240
Bentonite 200
1250
UBone Ash
OBlack Copper Oxide110 SUE’S CLEAR (Δ10 CLEAR)

HPERSIMMON (NOT STOCK GLAZE)550 Color: Transparent gloss icy greenish clear

Ingredients: Measurements in GRAMS

HColor: Glossy mottled red-brown G-200 feldspar 2500

ICG-200 Feldspar Whiting 2500

Ingredients: Measurements in GRAMS EPK 1800

WBone Ash 4860 Silica 3500

Silica 2160 Gerstley Borate 120

NWhiting 990 Tin Oxide 100

ETalc 630 720 TEMPLE WHITE
GRERed Iron Oxide
Color: Opaque satin creamy white, white to tan on stoneware

EPK 630 Ingredients: Measurements in GRAMS

1080 G-200 Feldspar 3470

EPK 2360

Silica 1890

Dolomite 1960

Whiting 310

9 10

***TENMOKU (No longer in use) YING CHING BLUE

Color: Gloss metallic brown to black Color: Transparent glossy light to medium blue

Ingredients: Measurements in GRAMS Ingredients: Measurements in GRAMS

Custer Feldspar 5100 G-200 Feldspar 4000

Silica 2370 Silica 3000

Whiting 1370 EPK 1000

EPK 630 700
Barium Carbonate
260 600
YZinc Oxide 260 310
LRed Iron Oxide 950 150
NBentonite 230 25
Dolomite

Strontium Carbonate
Whiting
Red Iron Oxide
Cobalt Carbonate
O***T-PET CLEAR (No longer in use)
Δ 04 Low-Fire GLAZES EColor: Transparent glossy clear slight green tint
SSilica
ANDREA GILL’S MAJOLICA
UPetalite
Ingredients: Measurements in GRAMS Color: Opaque semi-gloss white

3330
LWhiting
2380 Ingredients: Measurements in GRAMS
AEPK
2380 Frit 3124 6600

Kona F-4 Feldspar 1800
IONVAL CUSHING BLUE 1900
EPK 1000
Manganese carbonate 290
Nepheline Syenite 600
E TIngredients: Measurements in GRAMS
Zircopax 1500
L ACornwall Stone
Color: Matte blue to black where thick Bentonite 300

SA CWhiting
4600 CHINESE GREEN (NOT FOOD SAFE)
E UEPK
3400 Color: Texture matte pale green with copper flecks

Ingredients: Measurements in GRAMS
R EDVAL CUSHING GREEN 2000
Nepheline Syenite 975
Cobalt Carbonate 200
OM 4 Ball Clay 1875
RColor: Matte blue-green to black where thick
YIngredients: Measurements in GRAMS EPK Kaolin 1875
FO RCornwall Stone
Gerstley Borate 900

EWhiting Silica 1875

4600 Lithium Carbonate 375
T TEPK
3400 Copper Carbonate 225
O TTin Oxide
2000
N POWHITE SHINO DEB’S BASE
400
Color: Transparent gloss
Copper Carbonate 400
Ingredients: Measurements in GRAMS
EIngredients: Measurements in GRAMS
Frit 3195 4500

SNepheline Syenite Frit 3134 3000
Color: Opaque glossy orange salmon to white. Crawls when thick
EPK 2500
USpodumene
4500
OOM 4 Ball Clay DEB’S BLUE
1520
HEPK Color: Deep sea blue
1500
Ingredients: Measurements in GRAMS
Kona F-4 Feldspar 1080
HSoda Ash Frit 3195 3600
1000
IC***Winn’s Turquoise (No longer in use) Frit 3134 2400
400 (Dissolve in hot water)
EPK 2000

WIngredients: Measurements in GRAMS Copper Carbonate 200

Color: Semi-gloss turquoise Cobalt Carbonate 40
NKona F-4 Feldspar
EStrontium Carbonate 5000 DEB’S MOSS GREEN

EEPK 2730 Color: Translucent Light to medium mossy green

SilicaRDolomite 910 Ingredients: Measurements in GRAMS

GCopper Carbonate 910 Frit 3195 3600

460 Frit 3134 2400

280 EPK 2000

Bentonite 170 Copper Carbonate 200

Burnt umber 320

11 12

DEB’S ORANGE-RED JACKIE’S PEACOCK BLUE

Color: Orange-red Color: Semi-matte mottled peacock blue

Ingredients: Measurements in GRAMS Ingredients: Measurements in GRAMS

Frit 3195 3600 Gerstley Borate 3040

Frit 3134 2400 Lithium Carbonate 800

EPK 2000 Nepheline Syenite 400

Mason stain 6026 400 (Lobster encapsulated stain) EPK 400

Silica 3360
Bentonite 80
Copper Carbonate 240
YDEB’S PURPLE
LColor: Light to medium lavender
NIngredients: Measurements in GRAMS
OFrit 3134
Frit 3195 3600 KATHY’S AMBER
EEPK
2400 Color: Transparent glossy Honey amber
SCobalt Carbonate
2000 Ingredients: Measurements in GRAMS
L UFAT YELLOW
Mason Stain 6385 240 (Pansy Purple) Frit 3124 3000

24 Gerstley Borate 3000

Nepheline Syenite 2000
AColor: Translucent gloss Bright acid yellow
EPK 1000
NFrit 3124
Silica 1000

Ingredients: Measurements in GRAMS Red Iron Oxide 400
IOEPK
8500
E TMason Stain 6450
1000 KATHY’S TURQUOISE
L ABentonite
Flint 500 Color: Transparent glossy bright turquoise
ESA UC***HONEY AMBER (NO LONGER IN USE)
800 (Praseodymium) Ingredients: Measurements in GRAMS

300 Frit 3195 3000

Gerstley Borate 3000
R DIngredients: Measurements in GRAMS
Nepheline Syenite 2000

Color: Transparent glossy Honey amber EPK 1000
EFrit 3124
RGerstley Borate Flint 1000
YNepheline Syenite
2700 Copper Carbonate 200
FO REPK
2340

1800 KD CLEAR
ESilica
900 Color: Transparent gloss Clear
T TLithium Carbonate
900 Ingredients: Measurements in GRAMS
O TRed Iron Oxide
360 Frit 5301 1430
N O***JACKIE’S BASE (NO LONGER IN USE)
540 Gerstley Borate 5350
PColor: Opaque satin
Silica 1430

EGerstley Borate EPK 2860

SLithium Carbonate
Ingredients: Measurements in GRAMS KRAWL BLUE/PURPLE (NOT FOOD SAFE)

3800 Color: Textured opaque dry stony matte Turquoise to cobalt blue
UNepheline Syenite
1000 Ingredients: Measurements in GRAMS
OEPK
500 Barium Carbonate 4400
HBentonite
500 Nepheline Syenite 2000

Silica 4200 Lithium Carbonate 500
HJACKIE’S IVORY
200 Silica 1100
ICColor: Semi-matte pearlescent ivory
EPK 2000

WGerstley Borate Copper Carbonate 700

Ingredients: Measurements in GRAMS PAD ALGAE (NOT FOOD SAFE)
NLithium Carbonate
ENepheline Syenite 3040 Color: Textured sulfur yellow to black

ESilica 800 Ingredients: Measurements in GRAMS

RBentonite 400 Lithium Carbonate 2090

EPK 400 Nepheline Syenite 5600

GLight Rutile 3360 EPK 875

80 Magnesium Carbonate 40

320 Rutile 480

Zircopax 480 Chrome Oxide 240

13 14

***PAD BASE SNOW WHITE (NOT FOOD SAFE) NO LONGER IN USE BLACK SLIP

Color: Opaque crystalline matte snow white, runny Color: Matte Black to Brown

Ingredients: Measurements in GRAMS Ingredients: Measurements in GRAMS

Lithium Carbonate 2625 Grolleg 2190

Nepheline Syenite 6335 Redart 2190

EPK 995 Kona F-4 Feldspar 2350

Magnesium Carbonate 45 Silica 1560

Bentonite 940
Pyrophyllite 780
Red Iron Oxide 500
Black Iron Oxide 300

Manganese Dioxide 300
Cobalt Oxide 100
YPAD DUSK
LColor: Light turquoise
NIngredients: Measurements in GRAMS
ONepheline Syenite
Lithium Carbonate 2090
EEPK
5600
SRutile
875 COBALT SLIP
UMason Stain 6319
Magnesium Carbonate 40 Color: Matte Blue

240
ALROB’S SATIN MATT BLACK
3000 (Lavender Stain) Ingredients: Measurements in GRAMS

Grolleg 4370

Kona F-4 Feldspar 2350
NIngredients: Measurements in GRAMS
Color: Opaque satin Black Silica 1560
IOG-200 Feldspar
Bentonite 940
E TZinc 400
2400 Pyrophyllite 780
L AGerstley Borate
Whiting 880 Cobalt Oxide 150

SA CFrit 3124
900 COPPER SLIP

Color: Matte Yellow to Gray
E UEPK 1920
Ingredients: Measurements in GRAMS
R DCopper Carbonate 800
Grolleg 4370
Manganese Dioxide 640
ERed Iron Oxide Kona F-4 Feldspar 2350
400
RChrome Oxide Silica 1560
FO RYWEIRD BASE 160
Bentonite 940
80
Pyrophyllite 780
EColor: Semi-transparent satin matte Clear
T TIngredients: Measurements in GRAMS Copper Carbonate 400

O TGerstley Borate KILN WASH

N PO***WOODYS TURQUOISE (NO LONGER IN USE)5000 Color: Matte White

Wollastonite 5000 Ingredients: Measurements in GRAMS

Alumina Hydrate 5000

EIngredients: Measurements in GRAMS Silica 5000

SFrit 3124 RED SLIP
Color: Transparent glossy bright turquoise
Color: Matte Red
UGerstley Borate
2700 Ingredients: Measurements in GRAMS
ONepheline Syenite
2340 Grolleg 2190
HFlint
1800 Redart 2190

EPK 900 Kona F-4 Feldspar 2350
HLithium Carbonate
900 Silica 1560
Δ 04-10 Low to High-WfireICSLIPSBARRY’S FISH SAUCE (HIGH FIRE SLIP BASE)
360 Bentonite 940

Copper Carbonate 180 Pyrophyllite 780

Red Iron Oxide 500

NColor: Matte White RUTILE SLIP
EIngredients: Measurements in GRAMS
EGrolleg Color: Matte Tan

Ingredients: Measurements in GRAMS

RKona F-4 Feldspar 4370 Grolleg 4370

GSilica 2350 Kona F-4 Feldspar 2350

1560 Silica 1560

Bentonite 940 Bentonite 940

Pyrophyllite 780 Pyrophyllite 780

Rutile 800

15 16

Δ04 Low-fire SLIPS RED IRON WASH

MARY BARRINGER Δ04 WHITE SLIP (LOW FIRE SLIP) Color: Matte Red to black
Color: Matte White
Ingredients: Measurements in GRAMS

Ingredients: Measurements in GRAMS Gerstley Borate 100

EPK 2500 Red Iron Oxide 167

OM 4 Ball Clay 2500
Nepheline Syenite 1500
1000
YFrit 3124 2500
LSilica
RUTILE WASH

Color: Matte Yellow to tan

Ingredients: Measurements in GRAMS
NKID’S SLIPS + WHITE SLIP
Gerstley Borate 100
OBlack
Rutile 167

EBrown 20%
Black Stain 6600
TERRA SIGILLATABlue 20%
Royal Blue Stain 6339 20%
SGreen 20%
Dark Brown Stain 6109 20% Directions for Mixing Terra Sigillata
You will need:
20%
20% Measuring cup
20% One-gallon container with lid
20% Length of clear rubber or plastic flexible hose
ULavender Lavender Stain 6319
Leaf Green Stain 6265
LTurquoise Turquoise Stain 6364
Purple Pansy Purple Stain 6385
AYellow
NPink
Praseodymium 6450
WASHES AND STAINS E TIONotes About Mixing Washes and Stains
L AAll these recipes are mixed into 1 pint of cold water to make a thin watercolor-like
SA Cconsistency. To make your own colored washes with stains, start with a 50:50 mix of

stain and Gerstley Borate and test. Add more Gerstley Borate if test is dry.
Deep Crimson6006 Directions:
1. Dissolve the soda ash in 1 cup of hot tap water then pour into the other 13
RE DUNotes About Application cups of cold water.
EWashes act like ink or watercolors and can be applied to bisque, over or under glaze. If
2. Blend clays into this water and mix well. Be sure to break up any lumps–use
a wash is applied to the foot of a pot it may pick up a little of the kiln wash when fired. a mixer if available. Can ball-milled for 6 to 10 hours.

R YA typical application is to paint washes over Majolica, but they work well over Temple 3. Let stand, undisturbed, for 24 hours.
FO Rwhite and White Shino as well. Wash can also be applied to the surface of bisqueware 4. Do not move the container, but carefully siphon off the uppermost, thinnest
Eand then wiped clean leaving residue behind in the recessed areas. Please note that
liquid. Draw liquid from the surface and allow air to draw occasionally in
washes are extremely concentrated colorants and will also act as fluxes in combination
order to check the thickness. As soon as the liquid thickens, stop siphoning.
T Twith glaze, often causing the glaze to run when applied heavily. This thin liquid drawn off the top is the Terra Sigillata. Dry the remaining
thicker liquid and discard.
5. Adjust through the addition or evaporation of water to measure 1.2, or less,

on a hydrometer, or visually like skim milk.

NO OTBLACK COPPER WASH Application:
PIngredients: Measurements in GRAMS
Color: Matte Black Terra Sigillata is applied to greenware with a soft brush. If you desire a burnished
EGerstley Borate finish, apply Sigillata to a bone-dry pot, a few square inches at a time. When the area
SBlack Copper Oxide 100 has lost its surface moisture but is still dark, rub with a soft cotton cloth, plastic bag
UBLUE WASH over your finger, the back of a spoon, or a stone. You may apply several coats, but
150
more than two can cause the Sigillata to flake. Terra Sigillata does not work well under
glaze because of its dense burnished surface making it less porous and less easy for
glaze to adhere.

OColor: Matte Bright Blue BLACK TERRA SIGILLATA
HGerstley Borate
Color: Opaque matte black

Ingredients: Measurements in GRAMS Ingredients: Measurements in GRAMS
HEPK
441 Redart 200

ICGREEN WASH 87.75 Manganese 10

Mason Stain 6339 220.5 (Royal Turquoise Blue Stain) Cobalt Carbonate 20

WColor: Matte Green- brown when thin Black Copper Oxide 10

NIngredients: Measurements in GRAMS Sodium Silicate 2 drops

EEPK Water 14 cups

GREMason Stain 6209 441 DARK BROWN TERRA SIGILLATA
Gerstley Borate
Color: Opaque matte dark brown
87.75
Ingredients: Measurements in GRAMS
220.5 (Chrome Green Mason Stain)
OM 4 Ball Clay 50

Albany Slip 50

Sodium Silicate 2 drops

Water 14 cups

17 18

GREEN TERRA SIGILLATA YELLOW TERRA SIGILLATA

Color: Opaque matte green Color: Opaque matte yellow

Ingredients: Measurements in GRAMS Ingredients: Measurements in GRAMS

OM 4 Ball Clay 200 OM 4 Ball Clay 180

Chrome Oxide 10 Vanadium 20

Sodium Silicate 2 drops Sodium Silicate 2 drops

Water 14 cups Water 14 cups
Repairs YLIGHT ORANGE TERRA SIGILLATA
LColor: Opaque matte light orange
NIngredients: Measurements in GRAMS
BISQUE REPAIR
ORedart
OM 4 Ball Clay 50 Uses: Used to repair cracks in bisqueware
ESodium Silicate
50 Ingredients:
USMAROON TERRA SIGILLATA
2 drops White Glue 50%

Water 14 cups Sodium Silicate 50%

add: EPK
LColor: Opaque matte maroon
Water until mixture is the consistency of mayonnaise.
AIngredients: Measurements in GRAMS
GREENWARE PATCH
NManganese
OM 4 Ball Clay 180 Uses: Repairs leatherhard clay cracks and breaks
IORed Iron Oxide
5 Ingredients:

Vinegar 1 teaspoon
E TWater 15
SAL CANAVY TERRA SIGILLATA Karo Syrup ¼ cup
Sodium Silicate 2 drops
Soda Ash pinch
14 cups
Nylon Fibers pinch
E UColor: Opaque matte navy blue
Powder Clay till pasty consistency

R DOM 4 Ball Clay
Ingredients: Measurements in GRAMS MAGIC WATER
EManganese
200 Uses: Aids to prevent cracking and supports joints.
RCobalt Carbonate
YCopper Carbonate 10 Ingredients:
FO RSodium Silicate
20 Sodium Silicate 3 tablespoons

10 Soda Ash 5 grams
EWater
2 drops Water 1 gallon
OT TT Glossary of Terms and Materials:ORANGE TERRA SIGILLATA
14 cups

N OIngredients: Measurements in GRAMS Information was collected from a combination of sources; see reference list and
PRedart bibliography on page 27.
Color: Opaque matte orange
Alumina Hydrate: (Al2O3 • 3H2O). A source of alumina used primarily for kiln wash
EWater 100 and wadding.
USRED TERRA SIGILLATA
Sodium Silicate 2 drops Aluminum Oxide: (Al2O3). Known as alumina, this oxide is used in glazes, promotes
viscosity, stability, gives hardness and durability.
14 cups
Ash Glaze: A glaze made with wood or vegetative-derived ash.
OColor: Opaque matte glossy when burnished Brick red
HNewman Red Ball Clay: A fine particle highly plastic clay usually high in iron. In glazes ball clays
Ingredients: Measurements in GRAMS add alumina but also iron thus darkening the glaze. In clay bodies it adds plasticity
HRedart because of its particulate size.
300
ICWater Barium Carbonate: (BaCO3). A secondary flux in stoneware glazes, most frequently
1200 used to produce a satin matte surface. Used in glaze to introduce the oxide, baria
which is an auxiliary flux in low and high-temperature glazes. Unsafe for low-fire
Soda Ash 15 functional glazes.
WWHITE TERRA SIGILLATA
14 cups Barium Oxide: (BaO). An auxiliary flux in earthenware frits and high-temperature
stoneware glazes. It is also introduced for its crystallizing properties which gives satin
NColor: Opaque matte glossy when burnished White mattes.
EIngredients: Measurements in GRAMS
EEPK Barnard Clay: A high iron-bearing earthenware clay, or a substitute for Albany slip.
RSoda ash 500
OM 4 Ball Clay

GWater 1000

15

14 cups

19 20

Bentonite: (Al2O3 • 5SiO2 • 7H2O) Is an extremely fine particle highly plastic colloidal Cobalt Oxide: (Co3O4). The oxide form of cobalt. The most powerful of the coloring

volcanic clay. It is used to lend plasticity to clay bodies and used in glazes to keep them oxides and also a strong flux. More coarse then its carbonate form.

in suspension. Coefficient of Expansion: The ratio of change of a material when heating and

Bisque: The first firing of greenware in preparation for glazing. The low firing cooling.

temperature (we fire our bisque to Δ06 or 1823°F) is sufficiently hard enough to Colemanite: See Gerstley Borate. (2 CAO • 3 B2O3 • 5H2O)
accept glaze without breaking.
Cones: (Δ) See Pyrometric Cones. See Chart on page 28.
Black Copper Oxide: (CuO). Coarser in grain size and yields more copper than
Copper Carbonate: (CuCO3). A main glaze colorant, copper compounds are capable
Ycopper carbonate. of producing a wide range of colors and is very responsive to atmospheric changes
LBlack Iron Oxide: (FeO). Ferrous oxide. inside the kiln.
NBlack Core: The dark grey center seen in shards, caused by a reduction atmosphere.
OWhen too much carbon is introduced the ceramic body weakens and creates other Cornwall Stone: Cornish stone. It is a feldspathoid material more complex than
Eproblems such as dunting and/or bloating. potash or soda feldspar and contains numerous trace elements.
SBlistering: Unwanted gassing of a glaze resulting in bubbles and craters of burst
Ububbles. Blistering occurs where the glaze has not had time to smooth out before it Crack: An unwanted break in greenware, bisqueware or glazeware. There are several
varieties of cracking; each has a uniqueness that aids in discovering the reason for it.
sets.
Crawling: A glaze defect (sometimes desired) characterized by the way the glaze
ALBloating: Blistering of the clay body caused by trapped gases. separates from the clay body and forms beading or bunching on the surface.
NBone Ash: Calcium phosphate. (Ca3 (PO4) 2). A high-temperature secondary flux in
Craze: Crazing is a common glaze flaw characterized by the development of fine
glazes. The essential ingredient in the production of bone china, giving it translucency. cracks in the finished glaze. It is caused by the glaze contracting more then the
ceramic body. It can also be caused from glazing thickness or cooling too quickly in
IOAn opacificier in low-temperature glazes. the kiln.
LE TBone China: An English form of china.
A ABorate: A chemical compound which includes the element boron. Cross-Draught Kiln: Cross-Draft Kiln. Natural-Draft Kiln. Horizontal kiln in which
ES UCBorax: A powerful flux in glaze. hot gases travel through the ware across the chamber, typical of wood fired kilns.
R DBurnishing: Polishing leatherhard clay by rubbing with a hard object like a smooth
Epebble or the back of a spoon. Custer Feldspar: See Potash Feldspar.
RBurnt Umber: A form of ochre with a significant manganese content.
FO RYCalcine: Through heating the material to red heat removes the chemically bonded Deflocculation: The action of dispersing the fine clay particles in a slip so that the
slip becomes more fluid through the addition of soluble alkalis.
water giving it the same chemical content without the additional shrinkage.
Dolomite: Calcium magnesium carbonate. (CaCO3 • MgCO3). A high temperature
T TECalcium Carbonate: Whiting. Limestone. (CaCO3) Carbonate of lime used to flux with a combination of calcium and magnesium. It has a matting effect in glaze
O Tintroduce calcium oxide into glazes, it is the most frequently used flux in high and promotes hard durable surfaces.

temperature glazes. Down-Draught Kiln: Down-Draft Kiln. A kiln in which the flames are deflected
downwards throughout the chamber to use the heat evenly before it exits out the
N POCasting Slip: A clay and water suspension used in the process of slip-casting. chimney located in the back or bottom of the kiln.
EChattering: The rhythmic rippling which appears when trimming. It occurs when the
Dunting: Cracking of pottery caused by stress which forms during firing and cooling,
clay is too hard or too soft or if the tool is not sharp enough or the wheel is turning to primarily caused by differential contraction of body and glaze or fast cooling.

Sfast. Earthenware: General name for wares made from low firing secondary clays
UChina Clay: See Kaolin. generally fired below Δ1 (2109°F). Pottery made of a porous body fired at a low
OChrome Oxide: Chromium Oxide. (Cr2O3). A colorant generally producing heavy temperature.
Hdark green colors. Chromium is found in chromate materials and is very refractory.
HClay: Hydrous Alumina Silicate (Al2O3 • 2SiO2 • 2H2O). All clay comes from Earthenware Clay: Common, usually red, ground clays. They contain many
ICdecomposed feldspathic rock. There are primary and secondary clays. Primary are impurities. Clays that are low in maturing temperature and used to make earthenware
clays.
those which are found at or close to their source and have a large particle size and are
Egyptian Paste: A self-glazing clay body which is fired to a low temperature.
Wrelatively pure. Secondary clays have been removed from its source through water,
Electric Kiln: A kiln that uses electricity to heat the chamber in a neutral to
wind or weathering making the particles finer, and it has absorbed impurities. oxidizing atmosphere.

ENClay Body: Is a clay composition designed for particular working characteristics. Engobe: Sometimes used interchangeably with slip, but it includes materials other
EClay bodies have 3 essential constituents 1) clay 2) flux (feldspar) 3) filler (silica, grog).than clay. An engobe is halfway between clay and a glaze and fires to a more vitreous
RCobalt Carbonate: (CoCO3). Standard blue colorant in glaze and slip. The most state.
Gpowerful of the coloring oxides and also a strong flux. More finely ground then the
oxide which gives a more even color. EPK: See Kaolin. Edward Plastic Kaolin. Mined in Florida.

Epson Salt: Magnesium sulfate: (MgSO4 • 7H2O). A flocculent used in glazes and

slips to help keep particles in suspension.

21 22

Eutectic: The lowest melting point of two or more substances that are combined and Jolleying: Forming a pot using a spinning mould which shapes the outside of the pot.
it is always lower than the melting point of any individual component.
Kaolin: China Clay. (Al2O3 • 2SiO2 • 2H2O). Very refractory. The purest natural clay
Feldspar: (K2O • Al2O3 • 6SiO2) Alumino-silicate mineral similar to clay, but and the essential ingredient in making porcelain. It has a coarse grain structure and
proportionally higher content of fluxes. The most important single glaze material in not very plastic. The coarse particle size is the result of its lack or erosion, as it is a
high temperature firings as it contains all three necessary constituents. primary clay found and mined at its source. A source of alumina in glazes.

Fireclay: Clay which has properties refractoriness or resistance to heat, though the Kona F-4: See Soda Feldspar.
varieties may vary widely in properties. They are relatively pure and free from iron
Kiln: A structure built to contain heat in order to turn clay into ceramic. There are
Yand have more coarse grain particles. many varieties of kilns from electric to oil to woodburning; though the effects are
LFiring: The process of converting clay to ceramic through heating until it becomes different the result is the same, turn clay into ceramic.
Nstone-like and unaffected by water.
OFlint: See Silica. (SiO2). Leatherhard: Cheesehard. The stage which plastic clay reaches during drying when
EFlocculation: The action of altering the physical properties of fine particles in a the clay can be picked up without distorting yet soft enough to work.
Ssuspension so that they no longer repel one another but aggregate into larger particles
Uand settle, a process used in the making of Terra Sigillata. Levigation: Refining clay by floating in water allowing the heavier particles to settle
LFlux: Any substance that lowers the melting point of a ceramic body or glaze. while the smaller particles are taken off. See Terra Sigillata.
AFoundry Hill Cream: See Stoneware clay. A stoneware clay that fires to a cream
Ncolor. Limestone: See Calcium Carbonate.
IOFrit: Frits are materials that have been combined and heated in glass and then
Lithium Carbonate: (Li2CO3). An active alkaline flux with similar color responses
shattered removing potential toxicity hazards. In clay bodies they strengthen and as sodium and potassium. Reduces glaze expansion and promotes crystallization.

E Timprove glaze fit, limiting problems of glaze defects and lowers the vitrification point.Lizella: A light red earthenware clay similar to Redart.
L AFrits are designated by a number which contain different materials.
SA CG-200: See Potash Feldspar. Low Temperature Firing: Is a range rather than one specific temperature. The
E UGerstley Borate: (1CaO • 1B2O3 • 5H2O). A flux used in glazes as a replacement for range generally varies from Δ022-Δ01.
R Dcolemanite.
EGlaze: A substance that melts to a glassy state at a given temperature. It is a layer of Lustres: Metallic surfaces on glazes applied on top of glazes and re-fired.
R Yglass which is fused into place on a ceramic surface. Through the process of heating it
FO Rrenders the ware food safe or gives the ceramic decoration. There are three necessary Macaloid: Magnesium alumino-silicate. A refined white variety of bentonite, though
not quite as plastic.
constituents for making a glaze, 1) Flux 2) Alumina 3) Glass-former.
Magnesium Carbonate: (MgCO3). A high temperature flux which produces a
T TEGold Art: See Stoneware clay. smooth, buttery, matte surface similar to Dolomite.
O TGreenware: Clay that is still in working condition and has yet dried sufficiently for
N Ofiring. Manganese Dioxide: (MnO2). Used in both high and low fire glazes and can be
PGrog: Fired fireclay or other refractory clay which has been ground to various degrees added to clay bodies.

of coarseness. In clay bodies it is used to counteract shrinking, warping and cracking. Mason Stains: A U.S. suppler of stains used as colorants in glazes, clay bodies, and
washes.
EGrog comes in a variety of mesh sizes usually considered Coarse, Medium, or Fine,
Sidentified by mesh size which corresponds to how many wholes in the screen per inch. Mid-Temperature Firing: Is a range rather than one specific temperature. The
U20-mesh is more coarse then 40-mesh which is more coarse then 60-mesh. range generally varies from Δ1-Δ6.
OGrolleg Kaolin: See Kaolin. An extremely pure English kaolin.
HHakame: A technique using slip applied with a wide often straw-like brush. Molochite: Porcelain Grog. The trade name for calcined china clay.
HHawthorne Bond Fire Clay: See Fire Clay.
ICHigh Temperature Firing: Is a range rather than one specific temperature. The Nepheline Syenite: (K2O • 3Na2O • 4Al2O3 • 8SiO2). Alternative to feldspar, it has a
very active fluxing powers, with a high sodium content which may cause crazing.
range generally varies from Δ6-Δ14.
Neutral Atmosphere: When the atmosphere inside the kiln is neither oxidizing nor
WHydrometer: Is an instrument used to measure the specific gravity of liquids; that reducing. Typically, an electric kiln fires in a neutral atmosphere going through bouts
Nis, the ratio of the density of the liquid to the density of water. of reduction and oxidation though predominantly the latter.
EEInlay: A decoration technique where lines are scored in clay and filled with another
Newman Red: See Earthenware.
color usually slip.
OM-4 Ball Clay: See Ball Clay. Old Mine #4 references which clay mine this
GRJiggering: Forming a pot by using a spinning mould which shapes the inside of the particular ball clay comes from in Kentucky.

Onglaze: Overglaze. Ceramic color applied on top of the fired glaze surface and given
an extra firing. The firing is at a lower temperature than the first glaze firing in order
that the first fired glaze is undisturbed while the onglaze color fuses onto the original
glaze surface.

Opacifier: Minerals which are included in glaze recipes for their ability to opacify a
glaze, make opaque.

pot. Oxidation Atmosphere: An atmosphere in a kiln where there is a plentiful amount

of oxygen enabling metals in clays and glazes to develop their oxide colors.

23 24

Paper Clay: A clay body that uses paper pulp as a filler to increase green strength. Saggar clays: Similar to fireclays and as smooth as ball clays, used as an addition to
Usually the recipe contains between 5 – 49%. stoneware, terra cotta, and earthenware bodies.

Pearl Ash: Potassium Carbonate. (K2CO3). A highly soluble form of potassium, Sgraffito: A decorative technique where one scratches through some contrasting
usually used in a fritted form. colored slip into the clay body beneath.

Petalite: (Li2O • Al2O3 • 8SiO). Feldspar-like material which contains lithium and has Shivering: A glaze defect in which slivers of glaze shear away form the pot, it is the
a similar response as nepheline syenite but less likely to craze. result of poor glaze fit as the glaze shrinks less than the clay body and is the opposite
of crazing.
YPin-hole: A small smooth-edged hole in a glaze surface, usually occurring when a
Lbubble of gas bursts on the surface during firing. Silica: Silicon Dioxide. Flint. Quartz. (SiO2). The main glass-former and the most
NPorcelain: A vitrified, white ceramic whose main ingredient is kaolin, fired to Δ9 or common source of silica in both glazes and clay.
Ohigher.
EPorosity: The ability of a fired body to absorb water. Slip: A mixture of clay and water used for coating clays, generally applied to the
SPotash Feldspar: This is the most common form of feldspar and is the type surface of greenware to change its color, texture and/or to add decoration. Because
Ugenerally used in glaze, having larger amounts of potassium than sodium. slip is made of clay it shrinks as the clay shrinks which allows it to be applied to wet
LPyrometer: An indicator of temperature inside the kiln which is display in the form and/or leather-hard clay. If applied to bisque do not apply too thickly as it will likely
Aof a gauge, dial, or digital display. crack and/or flake off.
NPyrometric Cones: (Δ) Developed in 1896 by Edward Orton Jr. Pyrometric cones
IOare used to measure the effects of time and temperature inside a kiln. They are made Soda Ash: Sodium Carbonate. (Na2CO3). The common source of sodium for glazes.

of ceramic material and experience heat the same was as the ware making them more Soda Spar: Sodium Feldspar. (Na2 O Al2O2 6SiO2) The second common form of
feldspar used as a body flux and in glazes as a silicate provider. Less common then
E Taccurate temperature gauge. See cone chart on page 28. potash feldspar though very similar in performance. Higher levels of sodium then
L APyrophyllite: (Al2O3 • 4SiO2 • H2O). A hydrous alumino-silicate material used to potassium.
SA Creplace some or all of the flint and feldspar in industrial tile clays. It brings about a
E Udecrease in thermal expansion. Sodium Silicate: Water-glass. (Na2SiO3) Sodium oxide and silica combined in equal
R DQuartz: See Silica. (SiO2) proportions and used as a clay deflocculant. Don Bendel says: “makes water wetter!”
EQuartz Inversion: Quartz Phase. The change in silica (alpha quartz and beta quartz)
R Ywhere the difference is in the angle of the silica-oxygen-silica bond which changes at Specific Gravity: See Relative density.
O1063°F. The change occurs every time crystalline quartz passes this temperature in
F Reither direction. There is a decrease in size which may cause cracks in the ceramic Spodumene: (Li2O • Al2O3 • 4SiO2). A lithium alumino-silicate, similar in behavior to
Ebody if it goes through this stage too quickly. There is a 2% increase in volume which petalite. Used in glazes and in flameproof bodies.
T Tis reversible upon cooling. This stage happens when the kiln is just starting to develop
O Tcolor. Stains: Prepared stains. Prepared oxides. Inorganic coloring agents usually
N ORedart: See Earthenware Clay. Earthenware Clay with a high iron content. purchased in powdered form for adding to bodies, slips, washes, and glazes.
PRed Iron Oxide: Ferric oxide. (Fe2O3). Iron is the most common and most useful
Ecoloring oxides. Stoneware: A hard, strong and vitrified ware fired to a high temperature in which
SReduction Atmosphere: Indicates an atmosphere where there is little oxygen due the body and glaze mature. Named for its physical resemblance to stone. 2109°F -
Uto the presence of an excess of carbon from an incomplete combustion process. The 2381°F (Δ6 – 14)

effect this has is to turn all the materials that were oxides back into their metal state. Stoneware Clay: Are clays that mature between Δ5 – 11. They vary in plasticity and
firing range and there is no great distinction between saggar, fire and stoneware clays.
HORefractory: Resistant to heat or capable of withstanding high-temperatures.
Strontium Carbonate: (SrCO3). A rare alkaline earth used as a flux in both a clay
Relative Density: (previously called specific gravity). Is expressed as a number for body and glaze.

Heach material which specifically represents the weight of a chosen volume of the Talc: Magnesium Silicate. (3MgO • 4SiO2 • H2O). A secondary flux in glazes and clay
ICmaterial. Since 1ml (cc) of water weighs 1 gram the relative density is the same as the bodies particularly in low temperatures. Promotes smooth buttery surfaces.

weight in grams of 1 cc of the material. Terracotta: Earthenware ceramics both glazed and unglazed. It comes from Italian
and means fired earth.
WRutile: (TiO2). A natural source of titanium, usually containing some impurities in
Nthe form of iron and occasionally chromium and vanadium. It is used to produce Terra Sigillata: Latin for “sealed earth”. A slip that has been refined by repeated
Emodified iron colors. It has strong effects on other colors. levitations and deflocculated. It has an extremely fine particulate structure and is
ESaggar: A refractory box used to protect ware from direct contact with flames and usually burnished to a high polish. Best if fired between Δ08-02.
Rgases. A secondary use is to produce an artificial atmosphere within the saggar
Gcreating localized reduction. Thermal Expansion: Expansion in volume of matter that is experienced in
conjunction with temperature change.

Thermal Shock: The stress created within a ceramic object by temperature change
caused by the shrinkage and expansion of the ceramic body.

Thomas Ball Clay: See Ball Clay.

Tile #6: See Kaolin. A type of kaolin mined in Georgia.

25 26

Tin Oxide: (SnO2). The most widely used opacifying agent. Used as a whitener for Orton Pyrometric Cone Chart
glazes and is good at all temperatures.

Up-Draught Kiln: Up-Draft kiln. A kiln in which the hot gases and flame pass
upwards through the ware to the chimney or just out of the roof.

Vanadium: Vanadium Pentoxide. (V2O5) Is used to produce yellow colors.

Vitrify: Is the hardening, tightening, and finally, the partial glassification of clay,
giving fired clay its hard, durable, dense and rock-like properties.

LYVolatilize: To change from a liquid or solid into a vapor.
NWedging: The clay preparation involving the kneading of clay to thoroughly mix and
Oexpel air bubbles.
EWhiting: See Calcium Carbonate.
SWollastonite: Calcium Metasilicate. (CaO • SiO2). A natural calcium silicate which
Ucan be used as a replacement for whiting and flint. Reduces firing shrinkage and adds

thermal shock resistance in bodies and glazes.

ALWood Firing: Firing clay into ceramic with the use of wood as a source of fuel and

decoration.

NXX Saggar: See Ball Clay.
IOZinc Oxide: (ZnO) A useful flux from mid to high temperature. Very active producing
E Tbrilliant, glossy, smooth, trouble-free glazes.
AL AZircopax: Zirconium Silicate. (ZrSiO4). Opacifier generally produce cool white glazes
S Cand adds to the fluxing action of the glaze. Zirconium compounds are more stable
E Uthan tin.
References and Bibliography: R R Y EDThe books listed below are excellent resources and are often the direct link to the
Oinformation contained herein.
F R-Bendel, Don, Rice, Paula. Ceramics. Flagstaff, AZ. Northern Arizona University.

E1998.
T T-Cushing, Val. Cushing’s Handbook. 3rd Edition. 1994
O T-Fournier, Robert. Illustrated Dictionary of Practical Pottery. 4th Edition. 2000.
N O-Hamer, Frank and Janet. The Potter’s Dictionary of Materials and Techniques. New

York: Watson-Guptill, 1991.

P-Hopper, Robin. The Ceramic Spectrum. Radnor PA: Chilton Book Company, 1984.
E-Peterson, Susan. The Craft and Art of Clay. Englewood Cliffs, NJ: Prentice Hall,

1992.

S-Pitelka, Vince. Clay: A Studio Handbook. Westerville, OH. The American Ceramic
USociety. 2001.
O-Rhodes, Daniel. Clay and Glazes for the Potter. Chilton Book Company, 2nd Revised
HEdition. 1996

-Rhodes, Daniel. Ed. Robin Hopper. Clay and Glazes for the Potter. Iola, WI. Krause

HPublishers. 3rd Edition. 2000.

-Rosenbaum, Allen. VCU Ceramic Department Technical Handbook. Richmond, VA.

GREENWIC2000
http://www.ortonceramic.com/resources/pdf/wall_chart_degreeF.pdf

27 28

NOTES: NOTES:

GREENWICH HOUSNEOTPOFOTTRERREYSEADLUECATIONAL USE ONLY

29 30

NOTES: NOTES:

GREENWICH HOUSNEOTPOFOTTRERREYSEADLUECATIONAL USE ONLY

31 32

NOTES: NOTES:

GREENWICH HOUSNEOTPOFOTTRERREYSEADLUECATIONAL USE ONLY

33 34

NOTES:

GREENWICH HOUSNEOTPOFOTTRERREYSEADLUECATIONAL USE ONLY

35 36