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The more plastic a clay is the more pieces of a given size can be made from a box (boxes are 20kg or 44 lbs). Each mug thus required 500g of pugged clay. These have been trimmed and engobed (using our standard L3954B cone 6 engobe) and are drying (the trimmings left over are enough to make about two more). Notice I have waxed the outers of some of the handles to slow their drying (to keep it in sync with the mug itself). M390 is likely the most plastic native Plainsman body. Although it was not overly soft I stiffened up the clay for ten minutes on a plaster bat to make it my ideal stiffness for throwing.
Wowzers! These are actually hand-made, not thrown on the potter's wheel. You can see the vertical join by the handle as it rotates. Her's is a simple concept: A red clay (M390) with a thin application of partially opacified matte glaze. She flaunts a bare red clay base, polishing it. You can find her easily on Instagram and google.
This is a calcium matte base (as opposed to the magnesia matte G2934). The clay is Plainsman M390. 5% Zircopax was added on the left (normally 10% or more is needed to get full opacity, the partially opaque effect highlight contours well). 5% tin oxide was added to the one on the right (tin is a more effective, albeit expensive opacifier in oxidation). The PLC6DS firing schedule was used.
This mug was thrown. But the handle was cast from L4005D, a recipe for an M390-compatible casting body you can make. The fired maturity of this (fired shrinkage and porosity) matches very well with M390. The casting process is superior for certain shapes and ware types (this sacrifices no casting properties because there is no iron oxide in the recipe, it uses Redart instead). These are strong, the handle on this glazeless mug endured a couple of good taps with a hammer and stayed solid. The body fires a little browner in color than M390, which is a product of using Redart, a low-temperature clay, but as long as ware is glazed it looks identical.