As with everything we do, Mayco’s goal is to help artists achieve the results they want.

There are numerous variables involved in creating a ceramic piece: the clay body, the choice of glaze, the glazing technique, the kiln atmosphere, and the firing temperature—these are some of the key factors that determine the final result.

The purpose of this publication is to identify the variables that can affect the results of Mayco stoneware glazes and to provide tips for use that will help you successfully incorporate them into your studio practice. Why?

So that the glazes work for you, not against you.

Since glazing involves many nuances, we have broken down the information into clear steps—from start to finish. The terms listed below are used throughout this publication.

GLOSSARY OF TERMS

Absorbency – the ability of clay to absorb and retain moisture within its structure.

Vitrified (Vitreous) – having a glass-like appearance or properties. This term is often used to emphasize that a fired, unglazed surface no longer absorbs moisture.

Food Safe – A term used by the FDA to indicate the permissible levels of lead and/or cadmium leaching from the surface of a fired glaze. If the levels do not exceed the standards, the glaze is labeled as “Food Safe.”

All Mayco glazes are individually tested and comply with FDA requirements.

Heat Work – the combined effect of temperature and firing time on a ceramic piece.

CLAY BODY

The choice of clay body is one of the most important factors determining how the glaze will behave.

White Stoneware

All the photos in the catalogs, posters, and color swatches are fired on white 5/6 cone stoneware. This clay contains little iron, so it has a minimal effect on the glaze color.

Red / brown / speckled stone mass

Applying glazes to iron-rich clays changes the color and surface of the glaze. It is always recommended to conduct tests to see how a particular glaze reacts with different clays.

BUILDING TECHNIQUE

The technique used to shape the piece affects the application of the glaze and the clay’s absorption.

The less the clay absorbs, the more glaze remains on the surface—the color becomes richer, and the glaze can flow more freely.

– Hand-built

Maximum absorption. We recommend applying 3 layers of glaze to achieve results similar to the Mayco samples.

– Wheel-Thrown

Medium coverage. Three coats are also recommended.

– Slip Castings

Minimal absorption. Two coats are recommended.

GLASS COATING METHOD (APPLICATION TECHNIQUE)

The glazing method you choose has a direct impact on the final result.

Mayco offers:

• liquid glazes (SW) – ready to use with a brush;

• dry glazes (SD) – intended to be mixed with distilled water and used for dipping.

Application with a brush

A soft, fan-shaped brush is recommended. The brush must be fully saturated with glaze to ensure an even coating.

We recommend applying 2–4 coats, allowing each coat to dry.

With some glazes, variations in color and texture can be achieved by changing the direction and thickness of the brushstrokes.

Soaking

Dry glazes are ideal for full coverage and combinations.

When mixed according to the instructions, a single soak usually produces a result similar to the samples.

Casting

It is especially recommended for crystalline glazes, as it allows for better control over the distribution of crystals.

FIRING STYLE

The combustion method can significantly affect the result.

Examples from Mayco:

• white stone mass,

• casting,

• Fired to Cone 6 in an oxidizing atmosphere.

Temperature, time, and atmospheric conditions have a significant impact. It is essential to test under your own conditions.

Furnace Environment

Clean shelves, a protective coating, and a clean furnace—these are the keys to success. Always use control cones.

Furnace Atmosphere

Mayco glazes are suitable for oxidation, reduction, wood-fired, salt, and soda firing. Not all glazes have been tested in all firing environments, so testing is necessary.

Temperature

These glazes are formulated for Cone 6, but most work well at temperatures ranging from Cone 5 to Cone 10.

Greater thermal stress = greater glaze flow, so allow for movement in vertical tests.

FOOD SAFETY AND INDICATIONS

All Mayco glazes are food-safe when used according to the manufacturer’s instructions.

Since it is impossible to test all possible combinations of glaze layers, the manufacturer of the final product is responsible for the safety of the items sold.

Some glazes:

• suitable for dishes,

• Suitable only when coated with a clear glaze,

• Not suitable for cookware, and this does not change even when coated with a clear glaze.

Read the Mayco STONEWARE guide in English: