Stylized black and white image of Kurt rising from a bluish purple band; wind blowing through his long hair and a bowl spinning above his upturned left hand.  Titled The Hairy Potter with his motto: "If you don't see what you want, he can probably make one materialize for you."

“Glaze” is a mixture of ingredients that, when fired to a predetermined temperature, melt into glass.  The chemistry of mixing glaze requires that enough of each basic ingredient (silica, alumina and flux) are combined so that the glaze actually melts but doesn’t run all over the inside of the kiln.  The fourth ingredients are colorants and glaze modifiers.  These affect the glaze color or  texture after the piece is fired.

I use glazes that are mixed by the technicians at Mudflat Pottery School, the studio where I work.  The type of firing I prefer uses a gas-fired kiln and is called “reduction”.  That is, when the kiln reaches the temperature where the glaze will melt, the atmosphere is modified so that there is more fuel in the fire than there is oxygen to burn it up completely.  This process draws oxygen out of the melted glaze and clay, and creates great variations in the finished work.

The three bowls shown to the right are all glazed with the same combination of glazes using the same application technique.  An amazing number of variables impact how a piece will turn out: the thickness of the glaze when applied, where the bowls were placed in the kiln, who did the firing. the barometric pressure, how the kiln gods were feeling . . .  As the potter, I have control over the shape of the clay and how I apply the glaze.  When the piece goes into the kiln, I have to relinquish “control” and accept what comes out.

Sometimes I get very lucky, as demonstrated by the spectacular bowl at the right.  I was expecting the glazes I applied to come out a light celadon green on the inside, and a darker teal outside.  I was told that the copper in the two glazes fumed over the piece during the firing to create the incredible bronze hue overall.  The crackling in the bottom is a characteristic of the celadon glaze.  The fuming copper was trapped in the cracks to create the dark lines you see in the basin of the bowl.

A two-thirds view of a fluted bowl primarliy showing the inside.  There are six panels of alternating color: a smeary looking crimson with highlights of blueish purple, the other a royal blue streaked with light blueish purple.

7.75 X 4 inch fluted bowl. 

A three-quarter view of 3similarly shaped bowls.  The range in diameter from 6 to 7 inches, but all have a fluted rim.  The bowls were all glazed with the same glaze combination and technique of application.  However, the finished results are dramatically different due to the reduction process of firing.  One is streaky sapphire blue with a white star burst basin; one is predominantly copper green with a streaky blue green basin; the last is an amethyst purple with a dark copper green and white star burst in the basin.

Three 6 inch fluted bowls all with the same glaze combination.

Three quarter and top views of a deep round bowl.  The inside is a dark old penny copper at the rim graduating to a lighter swirling smoky yet glowing bronze toward the center.  At the bottom there is a light copper-green center webbed with dark brown cracks.

13 inch by 6 inch bowl with copper-fumed glaze

This a three-paned picture showing a three quarter top, side, and engraved bottom views of a shallow fluted bowl.  The inside is a rich reddish purple background with an icy blue splash in the bottom. The side is frosty pinkish blue accented by the rich reddish purple that steaks down from the voluptuous rounded flutes to a dark blue band at the foot.  It is engraved for Jerel and Mascia 06-09-08.

13 inch bowl customized for a wedding present

This one-of-a-kind bowl was created by firing it twice.  I wasn't happy with the initial result, so I added a white glaze to the already fired blue piece that resulted in veiny white lines over the patchy blue ranging in shade from dark to light lapis.

13 by 5.5 inch bowl

Bakeware   Bowls    Glaze Results    Other    Pints    Plates    Platters