Commercial ceramic glazes from AMACO, Mayco, and Speedball are all formulated to melt into a glassy coating at specific cone temperatures, but they differ sharply in firing range, price per pint, color depth, and how reliably they survive repeated glaze firings in a home studio. This guide compares the three brands line by line, with…
Those tiny white specks on your fired bowl are not a kiln mystery. They are material lumps a 100 mesh sieve removes in about two minutes. This glaze testing guide covers the three habits that make fired results repeatable: making consistent test tiles, wet sieving every batch you mix, and measuring specific gravity before you…
Grog is crushed, fired clay that potters add to a clay body to reduce shrinkage, stop cracking, and help large work survive the kiln. The particles are hard, already-fired ceramic granules that do not shrink again when the clay around them dries and fires. This guide covers what grog is, how it works, its measured…
Cobalt carbonate is not blue in the bag. The powder arrives looking pink-lavender, and it only turns deep blue after it dissolves into molten glaze inside the kiln. That single chemistry surprise explains most color mysteries in pottery. This guide covers every classic ceramic colorant and oxide, including iron, cobalt, copper, manganese, chromium, rutile, titanium,…
Every ceramic glaze is glass, and glass needs exactly three raw materials to form: kaolin for stability, feldspar as the melting engine, and silica as the glass itself. Remove any one of the three and the batch fails in the kiln. Get the ratios right and you control gloss, durability, and fit at temperatures from…
Ceramic glaze is not paint. It is a thin layer of engineered glass built from powdered rock, melted onto clay at cone 6 (2232°F / 1222°C) or cone 10 (2345°F / 1286°C). Understanding ceramic glaze chemistry means learning three ratios and nine metal oxides. This guide explains silica glass formers, kaolin stabilizers, feldspar and carbonate…