Reduction speckle: a product of iron particles in the body

Monday 20th April 2015

In reduction firing, where insufficient oxygen is present to oxidize the iron, natural iron pyrite particles in the clay convert to their metallic form and melt. The nature of the decorative speckled effect depends on the size of the particles, the distribution of sizes, their abundance, the color of the clay and the degree to which they melt. The characteristics of the glaze on the ware (e.g. degree of matteness, color, thickness of application, the way it interacts with the iron) also have a big effect on the appearance.

Pages that reference this post in the Digitalfire Reference Database:

Iron Pyrite, Reduction vs Oxidation Glazes, A magnesia speckle matte at cone 6 oxidation is impossible, right? Wrong!, Reduction Speckle, Reduction Firing

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