I took John's Basic Glaze Chemistry and Raw Materials workshop a few years ago, and let me tell you, it was AMAZING! This man is a walking glaze encyclopedia! I didn't think it was possible to learn so much information in such a short amount of time. Before I took John's class, I could follow a glaze recipe (ie measure and mix the listed ingredients) but if something went wrong, or I wanted to change something, I had NO IDEA how to proceed. It was like baking without knowing what flour, sugar and baking soda do. But after John's class, I had a much, much clearer understanding of what was happening and a great foundation for building my glaze palette.
|Just a few of the Cone 04 glaze tests from John's Basic Glaze Chemistry Class|
John has been a potter and teacher for over 26 years. He lives in mountains of western North Carolina although he grew up in Dayton, Ohio. John is primarily a self-taught potter who has worked and taught at universities, colleges and craft centers across the country, including the Penland School of Crafts where he served as the Clay Coordinator and then, as the Studio’s Manager.
He is the author of the “The Complete Guide to High-Fire Glaze; Glazing & Firing at Cone 10” which was published by Lark Books in 2004, was the juror for the book; “500 Bowls”, Technical Editor for “The Art and Craft of Ceramics”, and has written numerous articles for ceramics publications including: Ceramics Monthly, Ceramic Review, Studio Potter, Clay Times, New Ceramics, Ceramic Technical and The Log Book.
He is currently a studio potter in Bakersville, North Carolina and teaches glaze chemistry, throwing, glazing and firing workshops.
Here is the glaze (and fun story) that John is sharing with us today...
This is one of my favorite chairs. I formed it with the wire cut method, where you take a block of clay
and cut out the chair shape. (http://www.youtube.com/watch?v=gvfyD5xJobI)
Then I bisque fired the chair to cone 05. Then I rakued it with the glaze Raku Turquoise:
Raku Turquoise (From Chappell’s Book)
42.5 Frit P-25
27.4 Frit 3134
9.8 Lithium carbonate
4.5 Copper Carbonate
I then glued them back on and this became my favorite chair because it had the interplay of the
different glazes within the same piece.