Goerg & Schneider Clay 441 – 45% Grog, White Firing

Goerg & Schneider Clay 441 – Hand-Building Clay with 45% Grog for Large Pieces and Raku

Clay 441 from Goerg & Schneider is an earthenware body that fires white to light cream, for hand building larger ceramic objects. It contains 45% grog with a particle size of 0.2 to 0.8 mm. The grog gives the clay support as you work, so your piece keeps its shape better. According to the manufacturer, the special grog is low-dust and the clay is particularly suitable for large-format pieces.

Thanks to its high thermal shock resistance, the 441 is also often used for raku firing. The recommended firing range is 1000 to 1180 °C.

Who and what is the 441 suitable for?

The clay is aimed at anyone who builds or models by hand: larger vessels, sculptures or decorative objects using slab or coil techniques. It also suits first larger pieces, because the grog gives the clay extra support. However, the grog remains clearly noticeable when working and on the surface. If you want a particularly smooth surface or very fine throwing work, a finer throwing clay is the better choice. You can also use the clay without raku firing; choose the firing schedule and glaze to suit your project and the firing range.

Drying and firing

Let large or unevenly thick pieces dry slowly and as evenly as possible. At first, cover thinner areas loosely while thicker areas are still giving off moisture. Allow for about 4% drying shrinkage and, depending on the firing temperature, approx. 1 to 2% firing shrinkage. For raku work, a test piece is worthwhile before you fire a larger object.

• Firing range: 1000 to 1180 °C
• Water absorption approx. 12% at 1070 °C, approx. 9% at 1140 °C: the clay body remains absorbent

Goerg & Schneider Clay 441 product details

• Manufacturer: Goerg & Schneider, clay 441
• Clay type: earthenware body
• Application: hand building
• Fired colour: white to light cream
• Grog content: 45%, particle size 0.2–0.8 mm
• Recommended firing range: 1000–1180 °C
• Drying shrinkage: approx. 4% (at 110 °C)
• Firing shrinkage: approx. 1% at 1070 °C, approx. 2% at 1140 °C
• Water absorption: approx. 12% at 1070 °C, approx. 9% at 1140 °C
• Coefficient of thermal expansion: 71 × 10⁻⁷ °C⁻¹ (20–500 °C, fired at 1070 °C)
• Pack size: approx. 10 kg

You will also need: a kiln or other firing facility for bisque and glaze firing; glazes suitable for the firing range for glazing.