Pinholes in ceramic glaze are not random accidents. They are trapped gas bubbles that burst through the molten glaze surface during firing and fail to heal over before the kiln cools. Every pinhole tells you exactly what went wrong if you know how to read it. This guide covers every cause, the science behind why…
Crazing is not a firing mistake. It is a thermal expansion mismatch between your glaze and the clay body underneath it. That fine web of cracks across your glaze surface has nothing to do with underfiring or cooling too fast. The glaze simply shrinks more than the clay during cooling, and the tension creates the…
Ceramic glaze crawling has nothing to do with your kiln. The problem starts before the piece ever sees heat, and it is almost always fixable without changing your firing schedule. By the Numbers Glaze Crawling: What the Data Shows Sources: Studio potter surveys, Rhodes’ Clay and Glazes for the Potter, Digitalfire Reference Library 70% of…
Ceramic glaze is not paint. It is a glass coating that chemically bonds to clay at temperatures above 1,800°F, and when that bond fails, the defect always traces back to one of three root causes: formulation, application, or firing. This guide covers every common glaze defect (crawling, pinholes, blistering, crazing, shivering, bleeding, running, and more)…
Ceramic glaze is not a waterproof sealant that makes any pot food-safe. The glaze itself must be chemically stable to resist acid leaching from coffee, citrus, and tomato sauce before a mug or bowl can be safely used for daily dining. This guide covers low-fire, mid-fire, and high-fire food-safe glazes from major commercial lines including…
Ceramic glaze is not paint. It is a glass coating that fuses to clay at temperatures above 1,800°F, creating a permanent, waterproof surface that paint can never achieve. This guide covers every major ready-to-use glaze category for beginners: low-fire brush-on glazes, mid-fire dipping glazes, high-fire commercial options, specialty effect glazes (including crystalline, matte, satin, and…