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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
- 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
77C04E - 50:30:20 Frit 3134 cone 6 base
77E05B - Cone 10R Celadon - Luke Lindoe
77E06B - Lindoe Dark Celadon - Lower COE
77E14A - Cone 10R Red Mustard - Luke Lindoe
77E15A - Cone 10R Yellow Mustard - Luke Lindoe
84-G-05-S - Cone 10R Matte Crystal Iron - Luke Lindoe
G 304 - Cone 10R Crystal Iron Brown - Luke Lindoe
G1002 - LEACH'S CELADON CONE 10R
G1129 - MEDALTA CLEAR GLAZE CONE 8-10
G1214M - Hansen 20x5 Clear Cone 6 Base Glaze
G1214Z - Cone 6 Calcium Matte Base Glaze
G1214Z1 - Cone 6 Calcium Matte v2
G1214Z2 - Cone 6 Calcium Matte + TiO2
G1847 - Cone 10R Robin's Egg Blue
G1916M - COE Adjustable Low Fire Clear Glaze
G1916Q - Cone 05+ Expansion Adjustable Gloss Base
G1916Q2 - G1916Q glaze + 5% silica
G1916Q3 - G1916Q glaze + 10% silica
G1916QL - Cone 05+ Low Expansion Transparent glaze
G1916QL1 - Cone 05+ Lower Expansion glaze
G1916S - Cone 06-04 MgO Matte
G1916S1 - Cone 06-04 MgO (using talc)
G1916V - Cone 2 Clear (based on G1916Q)
G1916W - G1916Q with Iron Fining Agent
G1947U - Cone 10/10R Transparent Base
G2415E - Classic Albany Lithium Brown Glossy
G2415J - G2415E Alberta Slip Brown (less Li)
G2571A - Original Cone 10R Silky Matte Base Recipe
G2571B - Cone 10R Silky Matte Base (improved)
G2571BB - G2571B Rutile Bamboo
G2571C - Cone 10R Silky Matte Blue
G2571D - Cone 10R Silky Matte Red
G2571D1 - Cone 10 Marbled Red Glaze
G2571E - Cone 10R Silky Matte Black
G2576B - Cone 10R Tenmoku Glossy
G2584 - Cone 10R Blue Celadon
G2826A - 50:30:20 Gerstley Borate Cone 6 base
G2826A1 - 50:30:20 Frit 3134 base (fixed)
G2826A2 - 50:30:20 Gillespie Borate Cone 6 base
G2826A3 - 50:30:20 GB Makeover Pottery Glaze
G2826B - GB:Frit Raku Glaze
G2826F - GB Honey Amber 04
G2826G - GB Lavendar Satin Glaze Cone 6
G2826M - Gerstley Borate Antique Green Cone 5
G2826N - Gerstley Borate Raku Base NS/GB
G2826R - Floating Blue Original Cone 6 Glaze
G2826R1 - Floating Blue Using Gillespie Borate
G2826U - Floating Blue using Frit 3134
G2826V - Gerstley Borate Cream Oatmeal Cone 6 recipe
G2850C - Ravenscrag Cone 6 Black Glossy
G2850M-C - Ravenscrag Cone 6 Light Blue Matte
G2850P - TEAL BLUE CONE 6 KAT
G2851A - RAVENSCRAG SLIP Matte Blue - Cone 6
G2851AB - RAVENS FLOATING BLUE Cone 6
G2851D - KAT'S RC MATTE - Cone 6
G2851H - RAVENSCRAG Brown Gold Matte Cone 6
G2880 - Alberta Slip Tenmoku #1
G2880A - Alberta Slip Tenmoku #2
G2881B - Ravenscrag Alberta Slip Celadon
G2890B - Randy's Red Original Cone 6 Glaze
G2894 - Ravenscrag Tenmoku #1
G2894A - Ravenscrag Tenmoku #2
G2908A - Alberta Slip Floating Blue
G2917 - Ravenscrag Floating Blue
G2926 - Perkins Clear
G2926A - Perkins Clear with Frit 3134
G2926B - Cone 6 Clear Glossy Base
G2926BL - G2926B Cone 6 Gloss Black
G2926J - G2926B Reduced COE (Li2O)
G2926S - G2926B Reduced COE (MgO)
G2931 - Worthington Cone 06-2 Clear
G2931F - Zero3 Ulexite Transparent Glaze
G2931G - Zero3 G Low Expansion Low Fire Clear
G2931H - Zero3 H High Expansion Variant
G2931K - Zero3 K Cone 03 Transparent Glaze
G2931L - Zero3 L Low Expansion Variant
G2931L2 - Zero3 L Low Expansion w/F-69
G2932 - Deb's Clear #1 Cone 04-02
G2932A - Deb's Clear #2
G2933 - Gerstley:PV Clay low fire clear
G2934 - Cone 6 Magnesia Matte Base
G2934A - High Dolomite-Testing glaze
G2934BL - G2934 85:15 Adjustable Matte Black
G2934J - G2934 with ZnO for Brown Stains
G2934J1 - G2934 (glossed using ZnO)
G2934Y - G2934 (lower-LOI)
G2934Y1 - G2934Y (Anti-Crawling)
G2934Y2 - G2934Y (Higher COE/Stony)
G2934Y3 - G2934 Super Durable
G2934Y4 - G2934 Super Durable #2
G2934Z - G2934Y Red Using F-69
G2936 - Ravenscrag Low Expansion Cone 6 Base
G2936B - Ravenscrag Low Expansion White Base 2
G2936C - Ravenscrag Original Cone 6 Base Glaze
G2938 - Wright's Water Blue Base
G2941A - Leach's Satin Clear Original
G2941C - Leach's Satin Clear - Craze fix
G3806 - Panama Blue Cone 6
G3806A - Panama Blue 2 - More clay, Copper Oxide
G3806B - Panama Blue 3 - Copper Carbonate
G3806C - Panama Cone 6 Adjustment 2015
G3806D - Panama c6 - Lower COE #1
G3806E - Panama c6 - Lower COE #2
G3806F - Panama c6 - Lower COE #3
G3806K - Panama c6 - Lower COE #7
G3806N - C6 Fluid Clear Final Recipe #10
G3808 - Cone 6 Bright Clear - Shaun Mollonga
G3808A - Cone 6 Bright Clear using Frits
G3813 - Campana Cone 6 Transparent Glaze
G3813B - Campana Clear Lower Expansion #2
G3813C - Campana Clear Low Expansion (no Spodumene)
G3814 - Low Zinc High Feldspar Fritless base
G3822 - Spectrum Clear 700 Dipping Glaze
G3834 - Tenmoku Cone 6
G3840 - Shino Trial Number 1
G3868 - Gold - Cone 6
G3868A - Gold Using Spodumene
G3868B - Gold Using Fusion Frit 493
G3868C - Gold Using Frit #2
G3875 - Tangerine 4 (Orange)
G3875B - Zinc Clear cone 6
G3875C - Tangerine + Orange Stain
G3879 - Cone 04+ UltraClear Glossy Base
G3879C - Cone 04 UltraClear Low-Expansion
G3879E - Cone 04+ UltraClear Glossy Base
G3879F1 - Cone 04+ UltraClear Glossy Base
G3888 - Kieth Davitt High-fluid-melt copper blue
G3892 - Val Cushing Satin White #71
G3903 - Alberta Slip + Frit FZ-16
G3904 - Original Recipe Using Frit 3124
G3904A - 3134 Mistake Recipe Fixed
G3909 - Ravenscrag Cone 10R Matte Blue
G3910 - Fritted version of G1947U #1
G3910A - Fritted version of G1947U #2
G3912A - Surface Tension White Tin
G3914A - Alberta Slip Gloss Black
G3918 - Red Mustard in G2571A Base #1
G3925 - Perfect Clear
G3925B - Perfect Clear Make-Over #1
G3926B - G2926B with Tin/Zircopax
G3926C - G2934 White Tin/Zircopax
G3933 - G2934:G2926B Oatmeal - Cone 6
G3933A - G2934:G2926B Oatmeal Cone 6
G3933E - G3933 Oatmeal Ravenscrag #2
G3933EF - G3933 Oatmeal Ravenscrag #4
G3933G1 - G3933 Oatmeal Alberta Slip + Li
G3939A - Cone 6 Oxidation Marbled Red
G3948 - Red Orange Glazy Original
G3948A - Plainsman Iron Red Orange
G3948A1 - Red Orange - Plainsman Spodumene
G3948A3 - Red Orange - Plainsman Spodumene #2
G3955 - N505 Base Satin White - Opaque
G3966 - Cone 10R S2 - Luke Lindoe
G3971 - Lead Bisilicate Glaze
G3973 - Hilda Ross Rust
G4546 - Pattis Crystal Clear Cone 6
G4594 - 3B as a glaze
GA6-A - Oringal Alberta Slip Amber/Honey base
GA6-F - Alberta Slip Cone 6 Oatmeal
GR10-A - Ravenscrag Cone 10R Transparent Base
GR10-C - Ravenscrag Talc Matte
GR10-CW - Ravenscrag Cone 10R Talc Matte White
GR6-H - Ravenscrag Cone 6 Oatmeal
H0009 - 1945 MEDALTA FILTER CAKE
L2553B - Imco Carbondale Clay - C-Red
L2596E - H550 Casting Body #5
L2596F - H550 Casting Body #6
L2596G - H550 Casting Body #8
L2626 - Barnard Slip
L3127E - Boraq 1
L3127G - Boraq 2
L3127I - Boraq 3
L3127N - Boraq 5 #4 (available materials)
L3146A - Foundry Hill Creme+Nepheline
L3146B - New Foundry Hill Creme
L3146C - FHC + Kyanite
L3146D - FHC + Pyrax
L3164A - Cordierite Flameware - more bentonite, added grog
L3500 - Alberta Slip Original cone 6 base glaze
L3500G - Alberta Slip + Frit 3249
L3500H - Alberta Slip + Frit 3249 and Silica
L3523 - Cone 04 Gerstley Borate matte base
L3523A - Compare Boraq 5 #1 with GB in a glaze
L3523B - L3523 glaze using Boraq 5 L3127L
L3523C - L3523 glaze using Boraq 5 L3127M
L3523D - L3523 recipe using Boraq 5 L3127N
L3617 - Cornwall Stone substitute #2
L3619 - Cornwall Stone Average Analysis
L3660C - Flameware - Very High Pyrax with Molochite
L3660G - Pyrax/Kaolin Flameware
L3660P - Pyrax Flameware (low fire)
L3664A - PV CLAY Feb 2013 Shipment
L3673 - Laguna Barnard Slip Sub
L3685U1 - Zero3 Engobe Recipe
L3685Y - Cone 03 Terrastone 2 Engobe
L3685Z2 - Z2 White Cone 04 Engobe Base (no frit)
L3685Z3 - Z3 White Cone 04 Engobe (5% frit)
L3685Z5 - White Cone 04 Engobe for L4170B (3% frit)
L3685Z6 - Brown Engobe for Snow
L3685Z7 - Cone 04 Brown Engobe for Snow
L3685Z8 - White Cone 2 Engobe for L215, L210, L4170B (2% frit)
L3693E - Alumina Lining for Crucibles
L3693E1 - Zircon Lining for Crucibles
L3693H1 - Plastic Refractory Alumina Body H1
L3724N2 - Zero3 Stoneware
L3728 - Cone 6 Dolomite Testing Glaze
L3778D - Cone 6 Translucent Grolleg Plastic
L3778D1 - Cone 6 Grolleg Pink/Blue Porcelains
L3778G - Cone 6 Translucent Grolleg Casting
L3798C - M340 Casting Body
L3798G - M340C Casting Body Revision 7
L3802E - Crystal Ice - Cone 10
L3806L - Panama c6 - Lower COE #8
L3840 - Diatomaceous Earth (Ant Killer)
L3868 - Craft Crank - From PotClays, UK
L3868A - Craft Crank - Base
L3868C - Craft Crank Clone 2
L3869 - Crank Industrial - From England
L3869A - Industrial Crank Base
L3894D - PV Calc Mix 4
L3906 - P300 Cone 6 Casting Body
L3911 - Bizen Clay
L3916 - Bizen Duplicate using Plainsman Materials
L3924C - Zero3 Porcelain - Experimental
L3924J - Zero4 Plastic Porcelain
L3924L - Zero4 Casting Porcelain
L3954B - Cone 6 White Engobe Recipe
L3954F - Cone 6 Black Engobe
L3954J - Black Cone 10 Whiteware Engobe Recipe
L3954N - Cone 10 Engobe for H550
L3954R - Super-White Engobe for Cone 6
L3954S2 - White Engobe for M340, M390, L215, L210
L3972 - 98 Mix
L3977 - BGP Low Stoneware Body
L4001 - Plainsman Super Kiln Wash
L4005D - M390 Casting Version 5
L4023F - Proposed H440 Casting Body #5
L4028 - G2571A Rutile Bamboo
L4053B - Cone 6 Black Clay Body - Type 1
L4068 - Barnard Chemical Substitute
L4115J3 - L211 Stnwre 3D:OM4:NS
L4115L2 - L211 3D:OM4:NS:Talc 42 mesh
L4115L2a - L211 3D:OM4:NS:Talc 80 mesh
L4158 - Cimtalc 15 Talc lab test
L4159 - Cimtuff 9115 Talc lab test
L4163 - Red Art Cone 1 Clay Body
L4168G5 - H440C (concentrate) #5
L4168G9 - New H440 Functional Proposal #8
L4170 - L215 Terra Cotta Casting #1
L4170B - Terra Cotta Casting #2
L4170F - Terra Cotta Casting #3
L4208C - MNS Cone 6 Fine Stoneware
L4208D - 3B +200# particles sieved out
L4217G - M370-like Cone 6 Faster Casting
L4227 - Plus Clay
L4228 - Fimo Clay
L4239 - H550 Casting Body #7
L4244 - BGP Clay:Flyash F 50:50 Mix
L4244A - Flyash F:Bentonite 10:90
L4245 - LaFarge Fly Ash F:Bentonite 95:5 Mix
L4245F - Fly Ash F:Bentonite:BallClay 80:10:10
L4246 - A2 +200# particles sieved out
L4247 - A3 +200# particles sieved out
L4248 - Old Hickory M23 Ball Clay
L4249 - 3D +200# particles sieved out
L4249A - 3D MNS 325 Mesh
L4249B - 3D 100 mesh
L4264 - Raku Crackle Glaze Base - Frit 3110
L4264A - Raku Glaze Base #1
L4264B - Raku Glaze Base #2
L4264C - Raku Glaze Base #3
L4264D - Raku Glaze Base #4
L4273 - G3806N1 + 2% Zircopax
L4280 - L215 : M390 Mix for Cone 1 Stoneware
L4287 - Midfield Clay Yukon
L4287A - Catchment Clay Yukon
L4292 - Monte Marte Air Hardening Clay
L4293 - DAS Air Drying Clay
L4294 - Sculpey PE08 Oven Bake Clay
L4398 - Ravenscrag Cone 6 Raspberry
L4404A - Refractory Casting Slip
L4404B - Plastic Refractory (heavy duty)
L4404C - Refractory Plastic (low expansion)
L4404D - Refractory Casting (low expansion)
L4410L - L213 NS:Dolo 30:20
L4410P - L213 40:10 Dolo/NS
L4421 - Seed pelleting clay and binder
L4441A - Minspar
L4441B - Minspar Calculated Substitute
L4453C - 3D:A2 Body Base H550 Blend
L4458 - Lithium Flameware Test
L4482B - Alumina Wadding #2
L4484D - 2018 3B+6% 6666 at 100#
L4498 - Low Expansion Super White Cone 6 Fritware
L4498A - Low Expansion Fritware Casting
L4530 - Carbondale M390 #1
L4530A - Carbondale M390 #2
L4532A - Pyrometric cone pressing body #2
L4532B - Cone pressing body #3
L4532D - Cone pressing body #5
L4532F - Cone 5 Cone-casting v.1
L4543 - Firebrick & kiln post/shelf clay - v1.0
L4543B - Firebrick & kiln post clay v2.0
L4543C - Refractory kiln post clay v4.0
L4557 - Volumetric Screw Feeder Design - ESP32 based
L4558 - M390 Casting (M370+C-Red)
L4558A - M390 Cone 6 C-Red Casting #1
L4558B - M390 Cone 6 C-Red Casting #2
L4567 - Cat Litter
L4575 - SIAL Refractory Slip
L4575A - SIAL refractory slip Duplicate
L4588 - Red NZK Cone 6 Porcelain
L4597 - Luke Lindoe Fired Samples
L4599 - Slip for Slipware
L4599A - Slip for Slipware - #5 Ball Clay
L4608 - Kyanite Bisque-Fix, Kiln-Patch
L4655 - Titanium Dioxide in GA6-C
L4655A - GA6-C Titanium + Iron
L4655B - GA6-C Lower Thermal Expansion
L4696 - Cordierite Flameware
L4697 - Flameware body from French mfgr
L4705A - GA6-C Using Frit 3195 and Titanium
L4768D - Cone 6 Black Casting Body - Type 2
L4768E - Cone 6 Black Casting Body - Type 3.1
L4768H - Cone 6 Black Casting Body - Type 3.3
L4807 - M370-like Super-Fast Casting Porcelain
MHSCUL - MASTER RedArt Sculpture Clay
MRG6B - G2850A Ravenscrag Cone 6 Light Blue
MRG6C - Ravenscrag Cone 6 White Glossy
MRG6E - G2850P Ravenscrag Cone 6 Raspberry
MRG6G - G2851H Ravenscrag Cone 6 Light Blue Matte
P4738A - 98 BGP RETEST
P4808 - 45D
P5867 - Sculpture Clay
P6385 - M2 ST
P6821 - L215 Production Run - Mar 2020
P7088 - H440
PC-32 - Amaco Glaze: PC-32 Albany Brown
Insight-Live Shares (also referencing this recipe)
These add technical detail, development info, variations and improvements.
G1214Z1 - Cone 6 Calcium Matte v2
Modified: 2025-02-04 20:59:08
This glaze was born as a demonstration of how to use chemistry to convert a glossy cone 6 glaze into a matte.
| Material | Amount |
|---|---|
| Wollastonite | 27.00 |
| Ferro Frit 3124 | 36.00 |
| EPK | 20.00 |
| Silica | 5.00 |
| Calcined Kaolin | 13.00 |
| 101.00 | |
Notes
This is an adjustment to the original G1214Z recipe. The chemistry of this is the same, but the 37 raw kaolin in the original has been split to a combination of raw:calcined kaolin to reduce drying shrinkage (preventing cracking as it dries and crawling during firing). If unavailable, you can make your own calcined kaolin by roasting the powder in a container in a bisque firing.
Like G1214Z, this achieves a mat surface by incorporating a very high percentage of CaO in the chemistry. While visually appealing surfaces can be achieved, especially with slower cooling, leach testing should be done if metal oxide pigments are being used.
For 3000 grams we use 2600 water to get 1.45 specific gravity and good flow properties (no Epsom salts should be needed to gel the slurry, it is naturally thixotropic).
Related Information
5% titanium dioxide in G2934Y matte, G1214Z1 matte, G2926B glossy
This picture has its own page with more detail, click here to see it.
The body is Plainsman M390. The firing schedule is Plainsman PLC6DS.
Partially and fully opacified cone 6 G1214Z1 matte glaze
This picture has its own page with more detail, click here to see it.
This is the G1214Z1 calcia matte base (as opposed to the magnesia matte G2934). The clay is Plainsman M390. 5% Zircopax was added on the left (normally 10% or more is needed to get full opacity, the partially opaque effect highlight contours well). 5% tin oxide was added to the one on the right (tin is a more effective, albeit expensive opacifier in oxidation). The PLC6DS firing schedule was used.
G1214Z1 on M390 and Plainsman Coffee Clay at Cone 6
This picture has its own page with more detail, click here to see it.
Double-layered on top half. Fired with the PLC6DS schedule.
Titanium Dioxide in a cone 6 calcia matte glaze
This picture has its own page with more detail, click here to see it.
The glaze is G1214Z1 cone 6 base calcia matte on Plainsman M390 fired at cone 6 using the PLC6DS schedule. 5% titanium dioxide has been added. Titanium can create reactive glazes, like rutile, with no other colorants added. This effect also works well on matte surfaces, but the glaze needs good melt fluidity (that is good because functional mattes melt well). Calcia mattes host crystallization and work particularly well. Because titanium dioxide does not contain iron oxide lighter colors and better blues are possible compared to rutile (iron is still needed by it is coming from the body here). Like rutile, the effects are dependent on the cooling rate of the firing, slower cools produce more reactivity. Even application without drips is important (mixing as a thixotropic dipping glaze is best). This appearance also depends on using dark burning body or engobe.
G1214Z1 at cone 6 with 10% Zircopax and 5% tin oxide
This picture has its own page with more detail, click here to see it.
The body is Plainsman M390. The firing schedule is Plainsman PLC6DS. The tin is on the right.
Our base glazes plus opacifiers on a dark burning body at cone 6
This picture has its own page with more detail, click here to see it.
The body is Plainsman M390. These are commonly used base glazes. The top one is a magnesia matte, next down is a calcia matte. They react very differently to these additions. Notice also the difference when titanium dioxide is applied thickly. Tin oxide fires whiter than zircon (e.g. Zircopax). Each opacifier has issues. Tin is expensive. Titanium is difficult to mix into the slurry (screening required), not as white or opaque, variations in thickness produce more difference in results and it can turn blue. Zircon is more likely to cutlery mark, twice as much is required and it amplifies the color of any iron present.
A functional matte cone 6 glaze should melt as well as a glossy
This picture has its own page with more detail, click here to see it.
True functional mattes have fluid melts, like glossy glazes. They need this in order to develop a hard, non-scratching, durable glass. The mechanism of the G1214Z1 matte on the right is high Al2O3, it is actually melting more than the glossy G1214W on the left (this was fired between cone 5 and 6, it normally runs right off the runway).
Comparing two glazes having different mechanisms for their matteness
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These are two cone 6 matte glazes (shown side by side in an account at Insight-live). G1214Z is high calcium and a high silica:alumina ratio. It crystallizes during cooling to make the matte effect and the degree of matteness is adjustable by trimming the silica content (but notice how much it runs). The G2928C has high MgO and it produces the classic silky matte by micro-wrinkling the surface, its matteness is adjustable by trimming the calcined kaolin. CaO is a standard oxide that is in almost all glazes, 0.4 is not high for it. But you would never normally see more than 0.3 of MgO in a cone 6 glaze (if you do it will likely be unstable). The G2928C also has 5% tin, if that was not there it would be darker than the other one because Ravenscrag Slip has a little iron. This was made by recalculating the Moore's Matte recipe to use as much Ravenscrag Slip as possible yet keep the overall chemistry the same. This glaze actually has texture like a dolomite matte at cone 10R, it is great. And it has wonderful application properties. And it does not craze, on Plainsman M370 (it even survived a 300F-to-ice water IWCT test). This looks like it could be a great liner glaze.
Surface wrinkling of G1214Z cone 6 ceramic glaze
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The reason for this rather strange-looking wrinkling, experienced by one potter, is not obvious. But we are suspicious that the issue occurs at the application stage, and that substituting the calcined kaolin for raw kaolin in the recipe will thus resolve it. The G1214Z matte base glaze contains a high percentage of clay, kaolin to be specific. That can increase drying shrinkage enough for cracking to occur, leading to crawling. To reduce shrinkage we supply the kaolin as a mix of raw and calcined. The original recipe called for 36 kaolin, we supplied that with 20 EPK and 14 calcined kaolin. But that only adds up to 34, not 36. Why? Kaolin experiences a 12% LOI (weight-loss on firing). That means that 14 calcined kaolin supplies the same oxides as 16 raw EPK (14/0.88=16). Would this glaze work with 36 kaolin? For most people it would. As long as the bisque is porous enough to absorb water quickly, the glaze slurry does not have too much water and glaze is not applied too thickly. Adding a small amount of CMC gum, e.g. 0.1%, would also help if cracking occurs.
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G1214Z blue glaze from Lilly Ann Hume
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G1214Z golden glaze sample from Lilly Ann Hume
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1214Z over Ravenscrag slip at cone 6 gives mottled surface
Zircopax, tin oxide, titanium as opacifiers in four base glazes
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The body is Plainsman M390. Firing is the cone 6 PLC6DS schedule. Each horizontal row is a commonly-used base glaze. The top one is a magnesia matte, the next one down is a calcia matte, row 3 is G2926B glossy and row 4 is Ravenscrag Slip+frit. The two mattes behave very differently from each other with the additions of opacifier. Thickly applying an opacified glaze will obviously affect visual character (column 4). Tin oxide fires whiter than zircon (e.g. Zircopax). If you like the G2934 recipe, consider the G2934Y variant for better melting.
G2934 cone 6 DIY MgO matte glaze: Reliable, durable, adjustable, stainable
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These pieces were made from Plainsman Polar Ice and fired to cone 6 using variations on the PLC6DS and C6DHSC schedules. The dipping glaze is G2934Y, a recipe variant of G2934 having a finer micro-surface texture (it has the same chemistry but the MgO is sourced from a frit and talc instead of dolomite). These mugs display how well the recipe works with stains and the varying degrees of matteness we can achieve by varying the cooling rate and the percentage of glossy G2926B base blended in. As a magnesia matte, this glaze can have a surface that pleasant to the touch. It fires durable, can be quite matte without cutlery marking, and it has very good slurry and application properties (as a dipping glaze). It has a very low thermal expansion (won’t craze). It works really well with stains (except purples). It melts even better than the glossy!
G1214Z matte glaze melt flow
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This melt fluidity tester demonstrates that the cone 6 G1214Z recipe fires highly melt fluid, much more than one might expect from a matte glaze. When applied as a thin layer on pottery it does behave as a matte glaze. A quick look at its oxide chemistry reveals the reason: High CaO and a low Si:Al ratio. Unfortunately, many matte glazes are such simply because they are not melted enough. Others have to much SiO2 and require very slow cooling in the kiln to achieve results.
A potter fixes a leaching glaze problem
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G1214Z1 is a popular cone 6 calcia matte glaze recipe. It has very high melt fluidity, enabling a fine grained crystalline matte surface to develop during cooling. A potter was steered to this recipe after finding that G2934 magnesia matte fired too variegated when stained blue. However, her first effort with this failed a leaching test. She had a secret weapon: An account at Insight-live.com, where recipes and their calculated oxide formulas can be compared side-by-side. Leaching glazes are most often runny because they contain excessive fluxing oxides. She simply increased the SiO2, it is the glass that makes up the lion's share of all glazes (higher amounts of it characterize glossy glazes). Al2O3 couples with it to improve durability (and the Si:Al ratio is a factor in the degree of matteness). With an accompanying small increase in the B2O3, the magic glass:flux that makes most cone 6 glazes possible, the got the result on the right. The good news: It passed the GLLE test for leaching. There is a lesson here: She had to compromise the degree of matteness a little to get the food safe product. A benefit is that it is also less prone to cutlery marking. Happily, it turned out that much less blue stain was needed.
Mason stains in the G2934 matte base glaze at cone 6
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Stains can work surprisingly well in matte base glazes like the DIY G2934 recipe. The glass is less transparent and so varying thicknesses do not produce as much variation in tint as glossy bases do. Notice how low many of the stain percentages are here, yet most of the colors are bright. We tested 6600, 6350, 6300, 6021 and 6404 overnight in lemon juice, they all passed leach-free. The 6385 is an error, it should be purple (that being said, do not use it, it is ugly in this base). And chrome-tin pink and maroon stains do not develop the color (e.g. 6006). But our G1214Z1 CaO-matte comes to the rescue, it both works better with some stains and has a more crystal matte surface. The degree-of-matteness of both can be tuned by cooling speed and blending in some G2926B glossy base. You can mix any of these into brushing or dipping glazes.
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 |
The Right Chemistry for a Cone 6 Magnesia Matte
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| Articles |
Reducing the Firing Temperature of a Glaze From Cone 10 to 6
Moving a cone 10 high temperature glaze down to cone 5-6 can require major surgery on the recipe or the transplantation of the color and surface mechanisms into a similar cone 6 base glaze. |
| Firing Schedules |
Plainsman Cone 6 Electric Standard
Used in the Plainsman lab to fire clay test bars in our small kilns |
| Recipes |
G1214M - 20x5 Cone 6 Base Glossy Glaze
Developed by Tony Hansen in the 1980s. Its was popular for the simplicity and how well it worked with chrome-tin stains. |
| Recipes |
G1216M - Cone 6 Ultraclear Glaze for Porcelains
Substitute for low expansion cone 6 G1215U, this sources MgO from talc instead of a frit |
| Recipes |
G2928C - Ravenscrag Silky Matte for Cone 6
Plainsman Cone 6 Ravenscrag Slip based glaze. It can be found among others at http://ravenscrag.com. |
| Recipes |
G2934 - Matte Glaze Base for Cone 6
A base MgO matte glaze recipe fires to a hard utilitarian surface and has very good working properties. Blend in the glossy if it is too matte. |
| Typecodes |
Medium Temperature Glaze Recipes
Normally fired at cone 5-7 in electric kilns. |
| Typecodes |
Matte Glaze Recipes
Much less common that glossy glazes, normally have stricter firing requirements. |
| Typecodes |
INSIGHT Glaze Recipes
These are sample recipes included with INSIGHT software. |
| Glossary |
Matte Glaze
Random material mixes that melt well overwhelmingly want to be glossy, creating a matte glaze that is also functional is not an easy task. |
XML to Paste Into Insight-live
<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="Cone 6 Calcium Matte v2" keywords="This glaze was born as a demonstration of how to use chemistry to convert a glossy cone 6 glaze into a matte." id="3" date="2025-02-04" codenum="G1214Z1"> <recipelines> <recipeline material="Wollastonite" amount="27.000"/> <recipeline material="Ferro Frit 3124" amount="36.000"/> <recipeline material="EPK" amount="20.000"/> <recipeline material="Silica" amount="5.000"/> <recipeline material="Calcined Kaolin" amount="13.000"/> <url url="https://digitalfire.com/recipe/3" descrip="https://digitalfire.com/recipe/3"/> </recipelines> <urls/> </recipe> </recipes>
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