Different Clay types
Clay bodies
There are so many different types of clay out there it can be really confusing. Here’s a quick look at look into the different kinds of clay and how to use them.
Air-Dry Clay
This is a great clay to keep the kids occupied and doesn’t require a kiln to fire. However, it’s not waterproof so isn’t ideal for living outside. You can use normal paints to colour and seal the clay.
As the name suggests it dries using the air, which means as soon as you open the packet it will start to dry slowly.
You can use it in the same way as normal clay and can cut it, mould it and stick it together. Water is used to ‘rehydrate’ the clay if it starts to dry out and to help stick pieces together.
It has a smooth texture which is great for carving and adding texture.
Once it’s dried which can take a few hours or a little quicker if you leave it out in the sun, it’s ready for painting. Normal poster paints can be used, also ink pens, anything you have lying about the house. Varnish can help repel a little water but moisture in the air will always seep back in making it a little more fragile than other fired clays.
Earthenware
You have probably heard of or own some earthenware items. Despite the rise of stoneware and porcelain, earthenware remains artistically significant. Ancient Greek and Roman pottery, Hispano-Moresque ware (which evolved into maiolica and Delftware), and Chinese sancai are all earthenware.
Earthenware has achieved remarkable sophistication, exemplified by Liao dynasty luohans and Minton's majolica peacocks. 18th-century innovations like Wedgwood's creamware and transfer printing expanded earthenware's accessibility and popularity.
Terracotta, a type of earthenware, has a long history in sculpture, from Etruscan statues to Roman figurines, Tang dynasty tomb figures, and English Staffordshire figures.
Earthenware fires at relatively low temperatures (typically 600-1000°C), making it suitable for kilns with less precise temperature control, common in historical pottery production. It can be more suspectable to damage from moisture as it is often still absorbent, which is why you need to remember to put your plant pots away or off the ground in winter.
Stoneware
Stoneware is a type of pottery fired at a higher temperature than earthenwear (1100-1300°C), this higher firing results in a more dense and durable material. It was developed independently in various regions, including China, where it was widely produced alongside porcelain. In Europe, stoneware production emerged later, with Germany initially leading in its manufacture.
Stoneware is distinguished from earthenware by not only its higher firing temperature but increased vitrification, where the clay particles fuse together, forming a dense, non-porous structure. It can be used for various applications, including tableware, decorative ware, and industrial uses.
Stoneware is a common sight in modern kitchens, often found in the form of durable and stylish tableware. Plates, bowls, mugs, and serving dishes are frequently crafted from stoneware, appreciated for their strength and resistance to chipping. These items can be adorned with a variety of decorative techniques, including:
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Glazes: Stoneware is highly compatible with glazes, offering a wide range of colours, textures, and finishes, from glossy and vibrant to matte and earthy.
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Underglaze Decoration: Designs can be applied under the glaze, allowing for intricate patterns and colours that are permanently sealed within the ceramic.
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Overglaze Decoration: Decorations can be applied over the glaze, such as decals, hand-painted details, or metallic accents.
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Engraving: Simple yet elegant, engraving can create subtle patterns and textures on the surface of the stoneware.
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Slip Decoration: Applying coloured slips (liquid clay) to the surface before glazing creates interesting contrasts and textures.
These decorative techniques contribute to the aesthetic appeal of stoneware, making it both functional and visually pleasing.
Porcelain
Porcelain is a ceramic material renowned for its exceptional qualities, including translucency, strength, and fine-grained texture. It's created through a meticulous process involving the firing of carefully selected raw materials, primarily kaolin, at extremely high temperatures (typically between 1200°C and 1400°C) within a kiln.
This intense heat triggers the same vitrification process as in stonewear. Concurrently, within the ceramic body, the formation of the mineral mullite contributes significantly to the enhanced strength and translucency characteristic of porcelain.
Beyond its aesthetic appeal, porcelain finds diverse applications across various sectors. It's extensively used in the production of tableware, from delicate teacups and saucers to elegant dinner sets. Furthermore, it serves as a medium for artistic expression, adorning figurines, sculptures, and decorative objects.
Beyond its traditional uses, porcelain plays a crucial role in various technological and industrial applications. It serves as an essential component in the manufacturing of electrical insulators, laboratory ware, and dental prosthetics, highlighting its versatility and enduring significance in modern society.
Porcelain is renowned for its translucency and strength and boasts a rich history deeply intertwined with human civilization. Its origins can be traced back to ancient China, where over centuries of experimentation, potters gradually refined techniques to achieve the prized combination of whiteness, translucency, and durability.
By the Tang dynasty (618-907 CE), Chinese artisans had mastered the art of creating true porcelain, characterized by its high-fired nature and distinctive properties. This remarkable achievement spurred the spread of porcelain production throughout East Asia, and eventually, to Europe, where it captivated artisans and consumers alike.
The European fascination with Chinese porcelain fuelled a desire to replicate its unique qualities, leading to significant advancements in ceramic production within the continent. From the early attempts at soft-paste porcelain to the eventual mastery of hard-paste formulations, European potters dedicated centuries to perfecting their craft, contributing significantly to the diverse array of porcelain types available today.
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