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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

MGBase6 - Zinc Semimatte Glossy Base Cone 6

Modified: 2026-01-01 01:13:11

From page 98 of Mastering Glazes book

Material	Amount
Nepheline Syenite	36.00
Wollastonite	13.00
Zinc Oxide	10.00
EPK	10.00
Silica	31.00
Added
Cobalt Oxide	1.00
Rutile	6.00
107.00

Notes

While the authors of Mastering Glazes often prefer calcium-based mattes for stability, they included this zinc-based version for potters who want the buttery "low-luster" surface that zinc provides.

Key Properties
• Visual Appearance: A soft, muted teal or sage green. A semi-opaque with a soft, eggshell-like glow.
• Surface: It has a "stony" semi-matte texture. Because of the Zinc Oxide, it develops a micro-crystalline surface that feels smooth to the touch but lacks a reflective glare.
• Mechanism: The "Sea Green" hue is typically achieved through a combination of Copper Carbonate and sometimes a hint of Rutile or Iron Oxide to soften the copper's natural "electric" green.
• Stability: It stays where you put it and doesn't run, making it very safe for the kiln.

Likes (Pros)
• Sophisticated Finish: The semi-matte surface makes the piece feel more like a natural stone object.
• Great for Sculptural Forms: Because it doesn't run or "pool", it holds the crispness of your clay work. If you have sharp edges or subtle finger marks from the wheel, this will cloak them.
• Pleasant Feel: Like the "Waxwing Brown," this is a "pet-the-pot" glaze. The zinc creates a surface that is very satisfying to hold, making it ideal for the exterior of tea bowls or tumblers.
• Reliable Fit: Zinc mattes fit standard stoneware bodies, meaning you are less likely to deal with the crazing issues, like those found in the "Raspberry" recipe.

Dislikes (Cons)
• Marking: If you use a stainless steel knife or spoon against the surface, it may leave a dark grey streak (like a pencil mark). For this reason, it is often used on the outside of bowls and the inside is lined with a glossy.
• Color Sensitivity: Copper-based greens can be sensitive to the kiln environment. If fired too hot, the green can "wash out" or turn a bit metallic/black in spots (a phenomenon called "copper wash").
• Application Thickness: If applied too thin, the glaze can look "starved" and dry, like a chalkboard. It requires a confident, medium-thick application to get the semi-matte "sea green" depth.
• Not Acid-Proof (Relative): Zinc-matte glazes are slightly more susceptible to "etching" from strong acids (like lemon juice) over many years compared to their high-gloss counterparts.

Related Information

Links

Articles	Why Textbook Glazes Are So Difficult The trade is glaze recipes has spawned generations of potters going up blind alleys trying recipes that don't work and living with ones that are much more trouble than they are worth. It is time to leave this behind and take control.
Firing Schedules	Mastering Glazes Cone 6 Six-step with controlled drops to 1000C and 760C
Typecodes	Recipes from Mastering Glazes Book Descriptions of these glazes often contain marketing terms over-the-top adjectives like “scientifically formulated”, “perfect”, “exceptional”, “beautifully”, “engineered”, “specifically designed”, “sophisticated”, “flying colors”, etc. Of course there are no perfect recipes to be discovered, they all inhabit spaces balancing a dozen different properties, tuning one most often affects one or more of the others. And, recipe is only one thing affecting the finished product, process factors can have even more influence on finished appearance and properties.
Typecodes	Medium Temperature Glaze Recipes Normally fired at cone 5-7 in electric kilns.

XML to Paste Into Insight-live

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By Tony Hansen
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