paper white

firing to cone 10 in oxidation

slow downfire at 50 deg F an hour in the interval 1850 deg F to 1700 deg F

slow downfire at 25 deg F an hour in the interval 1700 deg F to 1650 deg F

One hour hold at 1650 deg F

In my search for a smooth flat white surface suitable for sharp edged leaf prints or other line decoratons, I investigating moderate to high barium glazes.

Here are three glazes with the same alumina, silica, alkali metals and moderate Baria, with BaO equal to .4.

glaze 1 ba_limits_0 has CaO + MgO as the remaining bases.

glaze 2 ba_limits_1 has minimal CaO/MgO and SrO replacing CaO + MgO of glaze 1.

glaze 3 ba_limits_2 has minimal CaO/MgO and ZnO replacing CaO + MgO of glaze 1.

To the right of a picture of a pot with this glaze, is a close up of a magnification of a small section of the glazed pot.

The pots are small conical bowls ~3 inches in diameter.

these glazes look similar, white, opaque to translucent waxy matt.

The close ups to the right show differences in degree of translucence and distinct surface texture.

The close ups show what the fingers feel, glaze 1 feels almost a bit rough, glaze 3 is nearly silky, and glaze 2 is inbetween.



glaze ba_limits_0

Of the three glazes, this first glaze, ba_limits_0 has the highest translucence. It shows many popped bubbles at the surface which are not entirely healed.

There are massed raggedy artifacts, surface micro-crystals and dense tracks of bubbles visible beneath the surface.



glaze ba_limits_1

this second glaze, ba_limits_1 is translucent with a smooth surface. There are tracks of bubbles visible beneath the surface

The bubbles are not dense, nor are there visible crystals on the surface.



glaze ba_limits_2

this third glaze, ba_limits_2 has a lumpy textured surface with fully healed popped bubbles at the surface.

There are few visible bubbles beneath the surface. This glaze is the most opaque of the three glazes

so bubbles beneath the surface likely are not visible.



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