Goerg & Schneider Clay 371 – grey to black stoneware, 25 % grog, 10 kg

Goerg & Schneider Clay 371 – stoneware clay for throwing and handbuilding, firing grey to black

Clay 371 from Goerg & Schneider is a plastic, ready-prepared stoneware clay with 25 % fine grog (grain size 0–0.2 mm). You can throw it on the potter's wheel, including larger pieces, or use it to handbuild smaller pieces. It fires grey to black in the kiln and is not air-drying.

The fine grog makes the clay stable while keeping it plastic. When throwing, this gives you a fairly even surface. With a firing range of 1000 °C to 1240 °C, the clay suits many firing schedules.

Working and drying

For throwing, centre the clay as you would with any stoneware. The fine grain feels pleasant in the hands, and the grog supports the wall even on taller vessels. For handbuilding and modelling, use the clay in coils, slabs or as a free form. Let the pieces dry slowly and evenly so that they do not crack or warp. The clay is not air-drying and must be fired in a kiln.

Firing temperature and shrinkage

The fired colour depends on the temperature: fired low, you get light shades of grey, and as the temperature rises the clay body turns anthracite to black. The clay body shrinks by approx. 7 % during drying and by 3 to 8 % during firing, depending on the temperature. For this reason, make dimensions and fits, for example on lids, larger. At 1070 °C the clay body still absorbs 9 % water, at 1240 °C only 0.1 %. The higher you fire, the more vitrified it becomes.

Glaze and choosing a clay

On the dark clay body, light, transparent or semi-transparent glazes look stronger, more opaque or sometimes a different colour. Test them on a test piece at the intended firing temperature. Unglazed areas show the fired colour particularly clearly. Clay 374, at 0–0.5 mm, is coarser and intended for handbuilding. Choose 371 if you want to throw or would like a finer surface.

Goerg & Schneider Clay 371 product details

• Manufacturer: Goerg & Schneider, Clay 371
• Type: stoneware clay, plastic, ready-prepared, not air-drying
• Grog content: 25 %, grain size 0–0.2 mm
• Fired colour: grey, anthracite to black
• Firing range: 1000–1240 °C
• Drying shrinkage: approx. 7 %
• Firing shrinkage: 3 % at 1070 °C, 5 % at 1140 °C, 6 % at 1200 °C, 8 % at 1240 °C
• Water absorption: 9 % at 1070 °C, 5 % at 1140 °C, 0.1 % at 1240 °C
• Coefficient of thermal expansion: 65
• Weight: 10 kg

You will also need: a kiln for firing; for throwing, also a potter's wheel