Even before April starts, the Avurudu pola has started. And one of the main items they sell in it are pots. Pots have become very useful in the kitchen. Today, let’s find out what is this pottery industry and how pots and other pottery utensils are made.
The pottery process
The potterry process is the forming of vessels and other objects with clay and ceramic materials, which are fired at high temperatures to give them a hard and durable form. Major types include earthenware, stoneware and porcelain. The place where such products are made by a potter is also called a pottery.
Definition of pottery
The definition of pottery is “all fired ceramic ware that contain clay when formed, except technical, structural, and refractory products”.
Origins
Pottery is one of the oldest human inventions, originating before the Neolithic Period, with ceramic objects like the Gravettien culture Venus of Dolni vestonice figurine discovered in the Czech Republic. and pottery vessels that were discovered in Jiangxi, China. Early Neolithic and pre-Neolithic pottery artefacts have been found in Japan.
Ceramics are made by forming a clay body into things of the selected shape and warming them to high temperatures in a bonfire and induces responses that lead to permanent changes including advancing the power and rigidity of the object. Much pottery is purely utilitarian, but can also be regarded as ceramic art.
Clay based pottery
A clay body can be decorated before or after firing. Clay-based pottery can be divided into three main groups: earthenware, stoneware and porcelain. These require increasingly more specific clay material, and increasingly higher firing temperatures. All three are made in glazed and unglazed varieties, for different purposes.
All may also be decorated by various techniques. In many examples, the group apiece belongs to is immediately visually apparent, but this is not always the case. Historic pottery of all these types is often grouped as either ‘fine’ ware, relatively expensive and well-made, and following the aesthetic taste of the culture concerned, or ‘coarse’, ‘popular, ‘folk’or ‘village’ wares, mostly undecorated, or simply so, and often less well-made.
Cooking in clay pots became less popular once metal pots became available. Clay remained popular for those dishes that depended on the unique qualities of clay cooking. These dishes include biriyani, Sri Lankan curries and fish pickle.
Earthenware
The earliest forms of pottery were made from clay that were fired at low temperatures, initially in pit-fires or in open bonfires. They were hand formed and undecorated. Earthenware can be fired as low as 600 °C and is normally fired below 1200 °C. However, earthenware has had a continuous history from the Neolithic period to today. It can be made from a wide variety of clays, some of which fire to buff, brown or black colour, with iron in the constituent minerals resulting in a reddish-brown. Reddish coloured varieties are called terracotta, especially when unglased or used for sculpture.
Ceramic glase
The development of Ceramic glaze made impassable pottery possible, improving the popularity and practicality of pottery vessels. The addition of decoration has evolved throughout its history.
Stoneware
Stoneware is pottery that has been fired in a kiln at a moderately high temperature, from about 1,100 °C to 1,200 °C. It is stronger and non-porous to liquids. The Chinese, who developed stoneware very early on, classify this together with porcelain as high-fired wares.
Stoneware could only be produced in Europe from the late Middle Ages, as European kilns were less efficient, and the right type of clay less common. It remained a speciality of Germany until the Renaissance. Stoneware is very tough and practical, and much of it has always been utilitarian, for the kitchen or storage rather than the table. But ‘fine’ stoneware has been important in China, Japan and the West, and continues to be made.
Porcelain
Porcelain is made by heating materials, generally including kaolin, in a kiln to temperatures between 1,200 and 1,400 °C (2,200 and 2,600 °F). This is higher than the temperatures ued for the other types, and achieving these temperatures was a long struggle, as well as discovering what materials were needed. The toughness, strength and translucence of porcelain, relative to other types of pottery, arises mainly from vitrification and the formation of the mineral mullite within the body at these high temperatures.
Although porcelain was first made in China, the Chinese traditionally do not recognise it as a distinct category, grouping it with stoneware as ‘high-fired’ ware, as opposed to ‘low-fired’ earthenware. This confuses the issue of when it was first made.
A degree of translucency and whiteness was achieved by the Tang dynasty, and considerable quantities were being exported. The modern level of whiteness was not reached until much later, in the 14th century. Porcelain was also made in Korea and Japan from the end of the 16th century after suitable kaolin was located in those countries. It was not made effectively outside East Asia until the 18th century.
Clay - pottery industry in Sri Lanka
The pottery of Sri Lanka has a very long history. There is evidence about the history of pottery in Sri Lanka that goes back to the second century BC. It has become an unchanged tradition that was passed from one generation to another. There is evidence from the archaeological excavations at the Anuradhapura Gedige and Kandarodai in Jaffna. Pottery items in the early stages of Sri Lankan history have been found in the archaeological excavations done near Thissam-aharamaya. Many pottery items dated back to the second century BC. Some of them were imported from various places in the world. That proves that pottery items were one of the main goods which were traded in international trading in ancient Sri Lanka.
Materials
The main material that is used in the Sri Lankan pottery industry is clay. There are mainly three types of clay that are used for pottery. As a result of the large scale use, clay has become a scarce resource in Sri Lanka. Clay is mainly available in the areas of Nattandiya, Dediyawela, Boralas-gamuwa, and Meetiyagoda.
Most of the classic pottery villages are found near these clay deposits. But since the demand spreads in the country deposits can be found in other villages outside these clay deposits. Some potters find it difficult to obtain clay which increases the production cost.
Red clay is commonly available in
Sri Lanka. It is usually mixed with sand and grit. This type of clay is mainly used to make tiles and bricks.
But after clearing the dirt it is also used for pottery.
White clay is found as a large deposit. It cannot be used as raw material directly and needs to be mixed with other materials used in the pottery industry. Much of the time white clay is used to manufacture porcelain and ceramics.
Ball clay can be found in small deposits. The main component of the ball clay is kaolin. Boralesgamuwa and Mieeiyagoda areas are the main areas with large Ball clay deposits.
As this industry is considered as one of the most historical industries in the world, we must protect the industry and work for the well being of the industry.
Text & Pix:
Yashodhara Paranagama
9H,
Musaeus College
Colombo 7