What Is Stoneware?

by Mark Hemmingson

Stoneware is a type of pottery that is quite hard, holds liquids, is not easily broken, and rings when it is tapped.

It is a type of clay that forms a close bond with glazes. When fired the glaze and the clay become almost the same thing, which is why it does not chip easily. It’s durability has made it the favoured clay for making dinnerware and everyday pottery for centuries. Technically speaking, stoneware is similar in its composition to stones, which is where it gets its name. Both of them have gone through changes caused by heat. Of course, stones do this naturally and take longer to form, while stoneware is made of specific minerals added to clay, and is fired in 10 to 14 hours.

Stoneware was developed in China as early as 1400 BC, during the Shang Dynasty, and was improved upon in the Han Dynasty from 206 BC to 220 AD. Refinements were made as the centuries passed, and its influence spread throughout Asia. In the 1700’s it was exported to Europe. Meanwhile, the European discovery occurred in the 1400’s, probably in Germany where different forms of salt glazes were used to give it a hard lustre. When Asian stoneware was introduced in the 1700’s, Europeans tried to replicate it and were able to improve their product. From there stoneware gained ground and was widely fabricated especially in Germany, England and the Netherlands.

Other Types of Pottery

Ceramics is a general term that encompasses all types of pottery. Earthenware refers to pottery that is fired to a lower temperature, about 1650 to 1940 degrees F. Generally speaking it is porous and softer because it has not been fired high enough to vitrify (become like glass). Porcelain, on the other hand, is fired to a high temperature, from 2300 to 2500 degrees F. It is very hard and often translucent. Bone China, in the beginning, actually had animal bones added for its calcium content. It was first developed in Europe in the quest to discover the recipe for porcelain, and it became widely used in the ceramics industry. Stoneware is somewhere between earthenware and porcelain with a firing range from approximately 2185 to 2260 degrees F.

Bernard Leach and his Influence

While not exclusively related to stoneware, Bernard Leach is an important figure in modern day ceramics. In some ways he is the reason why stoneware is so popular today. Leach was raised in Hong Kong, and studied at the London School of Art. He travelled to Japan, studied with the great Japanese master Kanzen, and met a young potter named Shoji Hamada. In 1920 Leach and Hamada set up Leach Pottery in Cornwall. They fused traditional Asian pottery from Korea, Japan and China with traditional German and English methods. At first their work was not widely accepted, but in 1940 Leach published his seminal book, A Potter’s Book, in which he shared his philosophy of craft and technique. The book caused a breakthrough and a new pottery aesthetic was born on a popular level. Leach spent time in North America in the 1950’s, and his followers spread his influence across the US and Canada.

An important outcome of Leach’s approach was the birth of the modern pottery studio in which a single potter does everything needed to create a pot, from beginning to end. This differs from traditional studios where occupations are divided into specific tasks. Leach wanted the potter to experience the whole process, and bring the piece through from the original idea to the finished product. He also championed well-crafted, practical pottery suited for everyday life. Many who followed his approach found stoneware to be the ideal clay for their work as stoneware’s durability lends itself to the practical and usable everyday pot, and allows potters to explore their craft through a wide variety of items.

References include…
A Potter’s Book – Bernard Leach
Introduction to Ceramics – Graham Flight
The Potter’s Manual – Kenneth Clark
The Ceramic Spectrum – Robin Hopper
Wikipedia