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These mugs were fired in the same kiln load at cone 10R and have the same clear glaze, G1947U. The mug on the left is a Grolleg kaolin (52% Grolleg kaolin, 24% silica and 19% Mahavir feldspar, 5% bentonite). The one on the right is 15% M23 ball clay, 40% #6 Tile kaolin, 15% Nepheline, 25% silica, 3% bentonite. Clearly, the Grolleg porcelain fires so much whiter.
| Glossary |
Primary Clay
A clay deposit that is near the site of erosion and alteration. They have more mechanical impurities and fewer chemical and mineralogical impurities. Primary clays have larger particles and less plasticity. |
| Glossary |
Porcelain
How do you make porcelain? There is a surprisingly simple logic to formulating them and to adjusting their working, drying, glazing and firing properties for different purposes. |
| Materials |
Tile #6 Kaolin
The most plastic kaolin commonly available in North America, most suitable for making plastic porcelains. |
| Materials |
Grolleg Kaolin
A white burning kaolin from the UK, commonly used in porcelain bodies and as a glaze suspender. Sticky when wet, low plasticity. |
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