Granite produces a pure clay (called kaolinite). The more structured the kaolinite crystal, the higher quality its porcelain china.All clays come from igneous rock, once molten magma, pushing up from the earth's center, only to be trapped in domes, mixing with the gasses, boron and flourine. But pale, pure, and well-structured clay comes from granite.
Granite → Feldspar (further decomposed by CO2 + H2O) → Kaolinite, Quartz, Potash
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