Exploring the Potential of Existing Glazes

Have you been looking for new glazes to add to your glaze palette? If so, I have 99 different cone 6 glazes you can try.

That probably sounds like a lot to look through, but it’s really just 9 base glaze recipes plus 10 colour variations each.

These glazes came from a workshop I taught in Whitehorse, Yukon in 2019 (back before Covid when we could all gather and do fun creative things together). In case you’re not from around here, that’s in the northwest of Canada, north of BC and east of Alaska.

There were 18 lovely ladies who split into pairs and each pair made a 2000g batch of a base recipe and then split it into 10 cups and added a different colourant to each cup. They mixed and sieved and dipped test tiles from 3 different Plainsman clay bodies into each test.

We fired all the test tiles to cone 6 (some of them reached cone 7) and then we had a really fun kiln unloading and test tile organizing and photographing party.

The results were stunning and vibrantly colourful! There are glossy glazes, matte glazes and even a crawl glaze in many different colours.

Most of the base recipes are ones that I’m very familiar with from the studio where I work, so I knew that they would be great glazes at cone 6. I hadn’t seen all the colour variations before so it was pretty exciting!

Colour Run Results and Recipes on Glazy.org

When you take a base recipe and then add different colourants to it, it’s called a “Colour Run”. I’ve posted each base recipe with a photo of the whole colour run of test tiles for that base on Glazy.org. There’s also a photo of the list of colourants we used uploaded to each recipe.

I made a bookmarked collection of all the workshop recipes in Glazy so they’re easy to find all in one place.

The page will look like this:

Then you can click on a recipe to see the ingredients for the base glaze.

Say we want to look at “Sue’s Calcium Matte“. Click on the name of the recipe and you’ll be taken to that recipe’s page.

It looks like this:

You’ve got the base recipe on the left and then photos on the right. Click on the photos for a window to pop up and you can get a better look at the photo.

Here is the photo of Sue’s Calcium Matte colour run:

There are 3 columns of extruded, L-shaped test tiles that were fired upright, one for each clay body.

The 3 clay bodies used are Plainsman M370, Plainsman M340 and Plainsman M390. In this photo the M370 and the M340 switch back and forth a couple times. The whiter clay is the M370, the grey clay is the M340 and the dark clay is M390.

The flat square tiles on the very left are some bonus Plainsman Coffee Clay tiles that were tested with this particular glaze, but weren’t used for all the glazes at the workshop.

Also included in the photos on Glazy is this list of colourants and percentages that we used.

Each row represents a different colourant that was tested and the test tiles in the photo are organized to reflect the order of this list. So, starting at the top row in the photo, those light glazes are the base recipe with no colourants added.

Then, work your way down with the colourant list. The 2nd row has 5% Manganese dioxide added. The 3rd row down has 1% Copper carbonate. The 4th row has 3% Copper carbonate etc.

See how it works?

Here are the 9 colour runs. Click the image to expand and click the link below the image to go to the recipe on Glazy.

Seeing all the colours of a colour run together gives you an idea of the general tone of colours that are possible with that particular base recipe. If you like the overall tone of colours, you may want to explore that base recipe further by:

• using different concentrations/percentages of colourant to make the colours paler/lighter or deeper/darker
• adding opacifiers to remove transparency, whiten colours and/or promote micro-crystallization
• blending colourants together

The possibilities are endless.

Every base glaze is going to react differently and create different colours with each colourant, depending on which materials are in the base. For example, in some recipes, chrome turns the glaze green, in others it turns brown, and in others it turns pink.

I hope these tests inspire you to do some glaze testing of your own. You don’t have to use my recipes, you can take any recipe at all and remove existing colourants to get the base recipe. Then you can use my colourant list or design a colour run of your own by adding different percentages of the colourants you have available.

Have you done a Colour Run before? Do you want to try it out? Let me know how it went or any questions you have in the comments below.

Join my free community

If you love learning about and discussing glazes, I'd like to invite you to my free social learning Facebook group called Understanding Glazes with Sue. The group is full of videos and discussions about firing, mixing glazes and fixing various glaze issues. Please join!

5 Ways You Can Make Your Glazes More Amazing (using glaze chemistry)

If you’ve ever wished your glaze could be just a little more…

• cost effective
• green/red/blue/purple
• compatible with your other glazes
• matte/glossy
• stable/fluid

… then you don’t want to miss this free class!

Date: Sep 21, 2023

Time: 10:00am Pacific / 1:00pm Eastern / 6:00pm UK time.

A replay will be available to watch for a limited time if you can't make it live.

The Art of Glaze Chemistry

Learn how glazes are formulated by using the UMF (unity molecular formula) and glaze calculation software to:

• create different glaze surfaces like matte, satin or glossy
• get glazes to melt at different temperatures or ensure your glaze is being fired to the right temp
• create durable, functional glazes
• fine tune the colours of your glazes
• fix crazing and other thermal expansion issues

This is a deep dive into all the chemistry that's happening inside the kiln.

Registration open Sep 21-29, 2023.

Learn to Mix Glazes from Scratch

If you’ve never mixed a glaze from scratch before and want to learn, I teach an online workshop called Glaze Mixing Essentials where I show you all the steps to mix a glaze and then test a base glaze with multiple colourants. Click the link for all the details.

September sale: Save $30 if you register by Sep 30, 2023.