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BORY1 - Bory 1 Crystalline Glaze
CELECG - Celestite Crystalline Glaze
FAAO - Fa's All-Opaque Crystalline Glaze
FAC5 - Crystal Number Five Glaze
FO - Octal Crystalline Glaze
G1214M - 20x5 Cone 6 Base Glossy Glaze
G1214W - Cone 6 Transparent Base
G1214Z1 - Cone 6 Silky CaO matte base glaze
G1215U - Low Expansion Glossy Clear Cone 6
G1216L - Transparent for Cone 6 Porcelains
G1216M - Cone 6 Ultraclear Glaze for Porcelains
G1916Q - Low Fire Highly-Expansion-Adjustable Transparent
G1947U - Cone 10 Glossy transparent glaze
G2000 - LA Matte Cone 6 Matte White
G2240 - Cone 10R Classic Spodumene Matte
G2571A - Cone 10 Silky Dolomite Matte glaze
G2826R - Floating Blue Cone 5-6 Original Glaze Recipe
G2826X - Randy's Red Cone 5
g2851H - Ravenscrag Cone 6 High Calcium Matte Blue
G2853B - Cone 04 Clear Ravenscrag School Glaze
G2896 - Ravenscrag Plum Red Cone 6
G2902B - Cone 6 Crystal Glaze
G2902D - Cone 6 Crystalline Development Project
G2916F - Cone 6 Stoneware/Whiteware transparent glaze
G2926B - Cone 6 Whiteware/Porcelain transparent glaze
G2926J - Low Expansion G2926B
G2928C - Ravenscrag Silky Matte for Cone 6
G2931H - Ulexite High Expansion Zero3 Clear Glaze
G2931K - Low Fire Fritted Zero3 Transparent Glaze
G2931L - Low Expansion Low-Fire Clear
G2934 - Matte Glaze Base for Cone 6
G2934Y - Cone 6 Magnesia Matte Low LOI Version
G3806C - Cone 6 Clear Fluid-Melt transparent glaze
G3838A - Low Expansion Transparent for P300 Porcelain
G3879 - Cone 04 Transparent Low-Expansion transparent glaze
GA10-A - Alberta Slip Base Cone 10R
GA10-B - Alberta Slip Tenmoku Cone 10R
GA10-D - Alberta Slip Black Cone 10R
GA10x-A - Alberta Slip Base for cone 10 oxidation
GA6-A - Alberta Slip Cone 6 transparent honey glaze
GA6-B - Alberta Slip Cone 6 transparent honey glaze
GA6-C - Alberta Slip Floating Blue Cone 6
GA6-D - Alberta Slip Glossy Brown Cone 6
GA6-F - Alberta Slip Cone 6 Oatmeal
GA6-G - Alberta Slip Lithium Brown Cone 6
GA6-G1 - Alberta Slip Lithium Brown Cone 6 Low Expansion
GA6-H - Alberta Slip Cone 6 Black
GBCG - Generic Base Crystalline Glaze
GC106 - GC106 Base Crystalline Glaze
GR10-A - Pure Ravenscrag Slip
GR10-B - Ravenscrag Cone 10R Gloss Base
GR10-C - Ravenscrag Cone 10R Silky Talc Matte
GR10-E - Alberta Slip:Ravenscrag Cone 10R Celadon
GR10-G - Ravenscrag Cone 10 Oxidation Variegated White
GR10-J - Ravenscrag Cone 10R Dolomite Matte
GR10-J1 - Ravenscrag Cone 10R Bamboo Matte
GR10-K1 - Ravenscrag Cone 10R Tenmoku
GR10-L - Ravenscrag Iron Crystal
GR6-A - Ravenscrag Cone 6 Clear Glossy Base
GR6-B - Ravenscrag Cone 6 Variegated Light Glossy Blue
GR6-C - Ravenscrag Cone 6 White Glossy
GR6-D - Ravenscrag Cone 6 Glossy Black
GR6-E - Ravenscrag Cone 6 Raspberry Glossy
GR6-H - Ravenscrag Cone 6 Oatmeal Matte
GR6-L - Ravenscrag Cone 6 Transparent Burgundy
GR6-M - Ravenscrag Cone 6 Floating Blue
GR6-N - Ravenscrag Alberta Brilliant Cone 6 Celadon
GRNTCG - GRANITE Crystalline Glaze
- 25 Porcelain
L3341B - Alberta Slip Iron Crystal Cone 10R
L3685U - Cone 03 White Engobe Recipe
L3724F - Cone 03 Terra Cotta Stoneware
L3924C - Zero3 Porcelain Experimental
L3954B - Cone 6 Engobe (for M340)
L3954N - Cone 10R Base White Engobe Recipe for stonewares
MGBase1 - High Calcium Semimatte 1 (Mastering Glazes)
MGBase2 - High Calcium Semimatte 2 (Mastering Glazes)
MGBase3 - General Purpose Glossy Base 1 (Mastering Glazes)
MGBase4 - Glossy Base 2 Cone 6 (Mastering Glazes)
MGBase5 - Glossy Clear Liner Cone 6 (Mastering Glazes)
MGBase6 - Zinc Semimatte Glossy Base Cone 6
MGBase7 - Raspberry Cone 6 (Mastering Glazes)
MGBase8 - Waxwing Brown Cone 6 (Mastering Glazes)
MGBase9 - Waterfall Brown Cone 6 (Mastering Glazes)
TNF2CG - Tin Foil II Crystalline Glaze
VESUCG - Vesuvius Crystalline Glaze

L2000 - 25 Porcelain

Modified: 2025-01-22 22:10:22

Base 25x4 porcelain recipe

Material	Amount
Kaolin	25.00
Ball Clay	25.00
Feldspar	25.00
Silica	25.00
Added
Bentonite	3.00
103.00

Notes

The starting point for a cone 10 plastic porcelain. Such porcelains require about 25% silica for glaze fit and about 25% feldspar to achieve near zero porosity. The remaining 50% is clay to provide plasticity and workability. Bentonite, or whiter burning smectite or hectorite, are often added to improve plasticity.

The percentages of the ingredients are tweaked to adjust the degree of vitrification (e.g. more feldspar and less clay for better fired density and strength; more kaolin and less ball clay for better fired whiteness; more ball clay and less kaolin for better plasticity). Minor amounts of other materials can be added to further adjust working and firing behaviour (talc or frit to improve maturity, stain to adjust color).

The actual properties will also depend greatly on the brand-name, particle size and purity of materials used. Translucent porcelains employ 50% low iron and low titanium kaolins and zero ball clay. Plastic porcelains employ plastic kaolins. Finer mesh silica is often used to control thermal expansion behaviour. Potassium and sodium feldspars and nepheline syenite are selected based on price, availability, purity, fluxing power and their effect on various firing properties.

Lower temperature porcelains increase the feldspar (up to 40%) and reduce the clay content to achieve maturity. They can also employ small amounts of talc or frit to help. Because the clay percentage is lower they either need to increase the ball clay at the expense of kaolin or add more bentonite.

There are no short-cuts to creating a good porcelain from the materials available to you. It is vital to do the testing work to determine the best mix to produce the needed working and fired properties. The final recipe will always be a compromise between the fired properties needed and the cost (if money is no concern it is easily possible to produce a recipe that costs five times more). Almost always the fired property that must be sacrificed to keep costs down is fired whiteness. Plasticity is almost always sacrificed (since the single most expensive ingredient by far are white burning plasticizers).

Related Information

Links

Glossary	Maturity A term used in the ceramics industry to signify the degree of vitrification in a fired clay. Mature clays are dense and strong, immature ones porous and weak.
Glossary	Porcelain How do you make porcelain? There is a surprisingly simple logic to formulating them and to adjusting their working, drying, glazing and firing properties for different purposes.
Articles	Formulating a Porcelain The principles behind formulating a porcelain are quite simple. You just need to know the purpose of each material, a starting recipe and a testing regimen.
Materials	Bentonite Bentonite can make a clay body instantly plastic, only 2-3% can have a big effect. It also suspends slurries so they don't settle out and slows down drying.

XML to Paste Into Insight-live

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<recipe name="25 Porcelain" keywords="Base 25x4 porcelain recipe" id="138" date="2025-01-22" codenum="L2000">
<recipelines>
<recipeline material="Kaolin" amount="25.000"/>
<recipeline material="Ball Clay" amount="25.000"/>
<recipeline material="Feldspar" amount="25.000"/>
<recipeline material="Silica" amount="25.000"/>
<recipeline material="Bentonite" amount="3.000" added="1"/>
<url url="https://digitalfire.com/recipe/138" descrip="https://digitalfire.com/recipe/138"/>
</recipelines>
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By Tony Hansen
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