Small, three-sided pyramids built of materials that melt at a specified temperature. It’s made to melt at the same temperature as the glazes it’s used with. Cones show how far the melting has progressed. During a fire, cones are positioned just inside the kiln so that they may be seen via a peephole. The cones are one-time-use only and come in a variety of temperature ranges.

They’re assigned a number based on the temperature at which they melt. The cone utilized is frequently mentioned when describing the temperature at which a piece/glaze is fired. Cones 06 through 01 are normally in the low fire range, whereas cones 1 through 6 are in the intermediate fire range, and cones 7 and higher are in the high fire zone.