Left: A high-contrast photo of a cut across the cross section of an eight-month-old slug of Plainsman M370 pugged clay. Right: A cut of a just-produced material (which will exhibit the same pattern in eight more months). You can feel different stiffnesses as you drag your finger across this clay, these are a product of the aging process combined with the natural lamination that a pugmill produces. Clearly, the older material needs to be wedged before use in hand building or on the wheel.
The process of mixing a plastic clay by hand before forming it. Similar to kneading of bread dough, it is considered an essential step by most potters.
Ceramic glazes and clay bodies can host micro organisms. They can be just a nuisance, a source of worry or they can render a product useless. What should you do?