06/10/2026
Many have asked - so I'm reposting how I do Copper Matte.
There are many ways to do Copper Matte. It had always been on my bucket list and a Raku potter, and good soul, Joe Clark, got me started with a glaze and some instruction. A heartfelt thank you to you Joe Clark!
The glaze I use:
Red Copper Oxide. 78.26
Red Iron Oxide. 8.7
Ferro Frit 3110. 13.4
Lithium Carb. 40
Copper Carb. 50
Strontium Carb. 7.5
Several drops of liquid detergent - I bought a blender for $5 at a thrift store to mix.
Mark Mason substitutes Black Copper Ox. for the Copper Carb. and Barium Carb. for the Stronitum in his glaze.
There are many variations in doing Copper Matte… in firing method, combustibles used, time, temperature, etc. I want you to go on a journey of discovery... for your sake and self-gratification to uncover more information and illumination. Watch and rewatch videos for subtle clues, and search online for everything you can find on the subject.
The method I employ is the most volatile and hard-to-control method by its nature. Sometimes I get lucky and it works the first time perfectly, and sometimes I retire vases numerous times. The nice part in doing a re-fire is you only have to re-heat to 1300 to re-fire.
Initial firing - fire to 1875 to fuse the glaze, then almost turn off the kiln to lower the temperature because… I pull the vases at 1300 and place in a can, rather than can over the vase method. In the can I place some flat paper and sometimes line the sides of the can with paper. Don’t over-do the paper. Play, investigate, experiment! I typically have to ignite the paper sq**rting kerosene and sq**rt more to enhance the flame. I then set a timer depending on the size and thickness of the walls of the vase. TIME! - This is where only experience and then intuition come into play. Joe's initial instructions were 7 minutes and up to 10 for larger pieces.
My typical timing is 6.5 minutes and down to 5.5 on small light-weight pieces. The timer goes off!... I fully open (NOT BURP) the can... the piece is still coppery and then ALCHEMY AND EXPLOSION! The colors explode on the surface, very quickly! I have a hose with a sprayer attached in my other hand and do my best to capture the perfect moment with a spray of water. The tendency is to spray too soon rather than too late and that's a difficult tendency to change. You’ll see what happens and the method will teach you. It’s not for the weak at heart. It’s a frenetic dance when you fire 6-8 pots at once like I do. Be brave… if a putz like me can do it, so can you.
"Control is an illusion...but choice is possible".
To limit the carbon staining I have been trying to use paper other than newspaper. I think it has a beneficial effect in that regard.
To learn this technique, I set myself to it wholeheartedly. If you want to learn it then throw a whole lot of vases. I initially threw 40, and fired and re-fired.
Because I have tasted some results that blow my mind it’s hard to settle for just ok.
You will learn to not settle also.
