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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
L2000 - 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

Insight-Live Shares (also referencing this recipe)

These add technical detail, development info, variations and improvements.

G1214M - 20x5 Cone 6 Base Glossy Glaze

Modified: 2025-12-29 20:41:51

Developed by Tony Hansen in the 1980s. Its was popular for the simplicity and how well it worked with chrome-tin stains.

Material Amount
Wollastonite20.00
Ferro Frit 313420.00
Custer Feldspar20.00
EPK20.00
Silica20.00
100.00

Notes

This was originally developed during the early 1980s to demonstrate principles of glaze chemistry in creating a glaze base sympathetic to the development of chrome-tin pinks and maroons. Articles a videos about this were used as selling tools for Digitalfire Insight software.

This recipe was developed over the years and had many versions. We now recommend G2926B as a base instead.

Related Information

If your glaze can handle more silica and melt just as well then add it!


This picture has its own page with more detail, click here to see it.

The cone 6 G1214M glaze on the left melts well. Can it benefit from a silica addition? Yes. The right adds 20% yet still melts as well, covers better, is more glossy, more resistant to leaching, harder and has a lower thermal expansion.

G1214M, W, N, O and S with Mason stains


This picture has its own page with more detail, click here to see it.

This shows clearly how well the M version works with a chrome-tin stain compared to the others. However the 6100 brown stain works best in the N recipe (which have MgO). Notice also that the M has a higher thermal expansion than the others.

Ravenscrag oatmeal layered over black at cone 6


This picture has its own page with more detail, click here to see it.

This is GR6-H Ravenscrag Slip oatmeal over G1214M black on porcelain at cone 6 oxidation to create an oil-spot effect. Both were dipped quickly.

Ravenscrag Cone 6 GR6-H Oatmeal over 5x20 cone 6 black


This picture has its own page with more detail, click here to see it.

The black recipe was made using G1214M with 5% Mason 6666 stain. The oatmeal overlayer is 50% the thickness of the black. The more fluid under-black comes through leaving islands and vertical rivulets of the stiffer oatmeal. Good control of the glazing process is needed to get consistent results using this approach.

5x20 glaze used as a base for an overglaze


This picture has its own page with more detail, click here to see it.

The blue second layer here is 5x20 cone 6 clear with 2% cobalt oxide and 5% rutile. The base black glaze is 5x20 with 4% Mason 6666 stain.

Cone 6 black with a second layer of oatmeal glaze


This picture has its own page with more detail, click here to see it.

The underglaze is G1214M cone 6 black (adds 5% Mason 6666 black stain). Overglaze left: GR6-H Ravenscrag Oatmeal. Overglaze right: GA6-F Alberta Slip oatmeal. Both produce a very pleasant silky matte texture (the right being the best). Both layers are fairly thin. In production it would be best to spray the second layer, keeping it as thin as possible. It is also necessary to adjust the ratio of raw to roasted Alberta or Ravenscrag Slips to establish a balance between drying hardness but not too much drying shrinkage (and resultant cracking).

Stains that work better in some glazes and not others


This picture has its own page with more detail, click here to see it.

This demonstrates how the host glaze affects the color development of certain stains. Blue is stable in pretty well all glazes. But chrome tin pink (top row) is very particular that the glaze have the right chemistry (1214M is obviously best, it has the highest CaO and lowest B2O3). The 6100 brown works much better in the N and O base glazes (they have higher Al2O3). Stain companies have guidance on chemistry particulars and you can view the chemistry of your recipe in your account at insight-live.com.

Links

Articles G1214M Cone 5-7 20x5 glossy transparent glaze
This is a base transparent glaze recipe developed for cone 6. It is known as the 20x5 or 20 by 5 recipe. It is a simple 5 material at 20% each mix and it makes a good home base from which to rationalize adjustments.
Articles G1214W Cone 6 transparent glaze
The process we used to improve the 20x5 base cone 6 glaze recipe to produce G1214W.
Articles G1214Z Cone 6 matte glaze
This glaze was developed using the 1214W glossy as a starting point. This article overviews the types of matte glazes and rationalizes the method used to make this one.
Articles Bringing Out the Big Guns in Craze Control: MgO (G1215U)
MgO is the secret weapon of craze control. If your application can tolerate it you can create a cone 6 glaze of very low thermal expansion that is very resistant to crazing.
Firing Schedules Plainsman Cone 6 Electric Standard
Used in the Plainsman lab to fire clay test bars in our small kilns
Recipes G1214Z1 - Cone 6 Silky CaO matte base glaze
This glaze was born as a demonstration of how to use chemistry to convert a glossy cone 6 glaze into a matte.
Recipes G1214W - Cone 6 Transparent Base
A cone 6 base clear glaze recipe developed by deriving a recipe from a formula taken as an average of limit formulas
Recipes G2926B - Cone 6 Whiteware/Porcelain transparent glaze
A base transparent glaze recipe created by Tony Hansen, it fires high gloss and ultra clear with low melt mobility.
Typecodes Medium Temperature Glaze Recipes
Normally fired at cone 5-7 in electric kilns.
Typecodes INSIGHT Glaze Recipes
These are sample recipes included with INSIGHT software.
Typecodes Transparent Glaze Recipe
Transparent recipes can be difficult to develop because entrained bubbles, crystals and crazing are not hidden by color and opacity. In addition, they must be well melted to give good results. Generally transparent recipes are sought after as liner glazes or bases to which to add opacifiers and colors. Typically work is required to match a transparent glaze to a specific clay body.
Glossary Silica:Alumina Ratio
A formula ratio used to evaluate and predict firing properties in ceramic glazes.

XML to Paste Into Insight-live

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By Tony Hansen
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