Question:
What is a glaze?
Essential components
The essential components of a glaze are silica, fluxes, and alumina. Silica is the basis of most glasses. The melting point of silica is over 3000oF, so we add fluxes to lower the melting point of the glaze. Alumina is needed to keep the glaze from becoming too fluid when it melts. Feldspar provides all three of these compounds and is the main ingredient in most cone 10 glazes.
Cream Apricot
Cream Apricot
Cone 03
Oxidation
Potash Feldspar 30
Whiting 30
Kaolin 30
Titanium 10
*See Disclaimer*
Feldspar
Typically when formulating a glaze we'll start with a feldspar, add a flux to lower the melting point, add clay to help keep the raw glaze in suspension and to help make the glaze adhere to the bisqueware, and add flint to keep the glaze from crazing (crackling). Colorants and opacifiers are added after the base glaze has been tested. Creating new glazes takes long hours of mixing small batches and firing them on test tiles. The choice of ingredients and proportions can be guided by calculations or by using rules of thumb and trial and error. Usually it's a little bit of both.
Tomato Red
Tomato Red
Cone 03
Oxidation
Potash Feldspar 42.52
Slica 200# 18.9
Kaolin 6.3
Magnesium Carbonate (Light) 5.51
Whiting 6.3
Bone Ash (Synthetic) 10.24
Red Iron Oxide 10.24
*See Disclaimer*
Why Glaze?
Why should we glaze our pots? Historically, most pottery was glazed to increase its function. Glazing provides a hard, water tight, scratch resistant, and sanitary surface. In addition, a properly formulated glaze also strengthens a piece of ware. Glazing gives us more control over the aesthetics of our pieces. We can decide color, surface, and any decorative elements we want to add to our work. Finally, keep in mind that we don't have to glaze our pots. Raw clay can be quite beautiful, and it can be decorated in many ways that don't require glaze.
Dry Alligator
Dry Alligator: Raku Reduction. Not suitable for tableware! Bisque fire work to 1100o C. Mix glaze same day as firing. Apply glaze thickly Dribble glaze on thickly for effects. *see disclaimer*
Gerstley Borate 52.5
Nephelene Syenite 12
Bone Ash 23.5
Copper Carb 12
Blue semi matt to glossy
Blue semi matt to glossy
Matt and best if fairly thin, glossy if too thick. 1260-1280oC in normal reduction
potash feldspar NR 39,60
china clay 18,80
quartz 14,60
whiting 22,90
titanium oxide 4,20
cobalt carbonate 1,60
Mossy Green
Mossy Green
Cone 03
Oxidation
Potash Feldspar 33
Whiting 34
Kaolin 30
Cobalt Carbonate 1.3
Red Iron Oxide 4.0
*See Disclaimer*
Ceramics Frequently Asked Questions
What precautions should I take in the studio?
How do I fire an electric kiln?
What are some stoneware glazes?
What Precautions when using dry ingredients?
How do I apply opaque stains ?
What should I keep in mind when designing my studio?
What tools do I need to start potting?
How do I best promote myself and my work?
What safety aspect should I keep in mind when working with glazes?
What should I remember when firing the kiln?
How do I best publicise my business?
How do I make a simple plaster mold?
How do I fire overglazes/lustres?
How do I create fine feature lines?
How and when sholuld I apply underglazes?
Are they Water or oil base stains?
Are any two kilns are exactly alike?
Can I use sand to stop glaze running onto shelves
Does greenware need to be dry before loading?
What is the history of the Potter´s Wheel?
What is The History of the Way of Tea
What is Celadon (Cheong-Ja) - the Stuff of Kings?
What is an overglaze marbleizer?
Is there a trick toThrowing Porcelain?
What are some stoneware glazes?
What are some good tools for decoration?
How do I apply texture to my piece?
Do I need kiln wash for bisque?
How do I refire a glazed piece ?
What must I remember when Raku firing?
How do I add decoration to my ceramics?
How do I care for my elements?
Does over firing produce poor colour in coloured glaze?s
What are some Black Firing Tips and Tricks?
What is the safest way to pack my ceramics?
How do I do a reduction firing?
automatic kiln sitter, should I trust it?
What are some tips for draining a mold?
What safety measures should I take with Raku Firing?
How do I attach a bat to the wheelhead?
What tools do I need for ceramics
What are suggested plate clay weights?
What do I need to get started?
What tools do I need to make a coil pot
How do I fire ceramic bisque ?
How do I recycle batches of clay quickly
What is the correct firing time?
How to I prepare and make slabs?
What materials are toxic in Ceramics?
Can Crackle glazes be used for food?
How do I avoid S cracks in wheel thrown ware
How do I get the press onside?
What are the Approx. firing times?
Ho do I avoid pitting and pinholes?
How do I decorate my ceramics?
How do I Bisque fire in an electric kiln?
How do I decorate my ceramics?
How do I apply crackle glazes ?
What effects can I achieve with a brush?
How do I Drain small pour holes?
How do I care for my new Kiln?
can I draw directly onto a piece?
How do I fire different bodies?
What is the humming in my new kiln?
What should I remember when firing a new kiln?
how do I get the best results in glazing?
How do I prevent dirt on my greenware?
How do I accomodate Clay Storage in my studio?
How do I prevent sagging during firing?
How do I load my brush for applying underglaze?
Why should I use pottery plaster?
How do I prevent glazes from settling ?
How do I create a woodtone effect?
What are some Doing well Quotes?
How do I care for my elements?
How do I store my throwing tools?
What is the history of Ceramics?
Why do I get black spots in my glaze?
How do I load my kiln for a glaze firing?
| Guru Spotlight |
| Jolyn Wells-Moran |
