As we discussed in the beginning, there are so many varieties of clay available across the world in the earth’s crust. We can group them into main types according to their properties and usage in making ceramic products.
PRIMARY CLAY: China Clay - this clay is also known as KAOLIN because of its mineral origin from Kaolinite. It is popularly referred to as China Clay because it was originally mined in China. In forthcoming articles we will discuss more about China Clay.
SECONDARY CLAY: As we discussed earlier when primary clay is transported from its birth place and shifted to other locations by natural transporting agents like wind, river, stream etc, the physical and chemical properties change and it becomes Secondary Clay.
There are many varieties of secondary clays but as ceramists we are interested in three main groups based on the Heat resistant capacity of Clay:
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Refractary Clay
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Vitrifiable Clay
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Fusible Clay
In forthcoming articles we will discuss these major groups in detail and better understand their varying properties.
