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The fritware body is highly plastic and can be thrown very thin. At cone 04, this thin-walled mug did not warp even though it fired to a near-glasslike cross-section. The density and strength are amazing; it took about 30 hits with a hammer to break it, hitting it as hard as I dared without risking being cut (I was holding it by its handle). The whiter flecks are agglomerates of New Zealand kaolin (because of improper mixing of the slurry); later batches were much better.

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To a potter, it may seem impossible that a body can be this porcelain-like at such a low temperature. And that such a body can be as plastic as this is. Achieving these came at the cost of shrinkage, both drying and firing, 18% total (vs 14% of a Grolleg cone 10 porcelain). Using this Zero4 fritware, very thin-walled pieces can be thrown. The frit also produces a body having a higher thermal expansion, so it fits any low-temperature glaze we have tried. This glaze is G1916QL3 ultra gloss clear glaze on Amaco Velvet underglazes. The low temperature has another benefit: Very sharp edges on painted underglaze designs. Zero4 replaces my old Zero3 fritware with a body that works at a more common temperature. It also employs a tiny amount of blue stain to produce the bluish-white color. Like Zero3, you can also make this yourself.
| Glossary |
Zero4
The designation for a group recipes for body, glaze and engobe (by Tony Hansen), that potters can use to make low fire stoneware and fritware porcelain |
| Glossary |
Fritware
A porcelain with significant added frit. The frit matures it at a far lower temperature than typical. The strength mechanism is one of particle glass bonding rather than mullite development. |
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