Characteristics of Japanese Ceramics Raw Materials: Volcano Origin
The quality of ceramic clay depends 60% on the careful selection and management of raw materials. Ensuring consistent production of the same high-quality ceramic clay requires precise control of the raw material process.
Three Key Types of Raw Materials in Japan:
Japan’s unique geology, characterized by volcanic activity, plays a crucial role in the formation of its high-quality ceramic clays. Over millions of years, volcanic magma deposits weather and transform into fine clay.
High Plasticity Clay
Formed from volcanic granite, this clay is aged for 5 million years through a process of weathering and water exposure. It is highly plastic and resistant to weathering, making it suitable for ceramic production.Modeling High Plasticity Clay
This clay, also formed from weathered volcanic granite, is finely grained and ideal for use in modeling and prototype creation.Feldspar-Silica Compound
Weathered volcanic granite also produces a feldspar-silica composite, which acts as a flux in ceramic production.
Volcanic Origins of Japanese Clay:
Japan’s volcanic landscape has a direct impact on the raw materials used in ceramics. Volcanic granite deposits, aged over 500 million years at the bottom of freshwater lakes, provide the base for high-quality clays. These clays are rich in minerals, including feldspar and silica, which contribute to the unique characteristics of Japanese ceramics.
The Importance of Consistency:
Raw materials are natural products, and their composition can vary depending on the location and vein from which they are mined. To maintain consistency in the production of ceramic clay, frequent inspections are carried out both at the time of extraction and upon arrival at the clay factory. The clay is also washed to remove impurities, ensuring the same high-quality pottery clay is produced every time, even with variations in raw materials.
Geologic Process:
Japan’s coastline is dotted with volcanic craters. Magma formed beneath the bedrock of the Asian continent rises to the surface, creating volcanic eruptions that shape the landscape. Over millions of years, the weathering of volcanic granite and the action of wind and water have produced the fine clay deposits that are the foundation of Japanese ceramics.