Orton Standard Pyrometric Cones

Orton cones, made by Orton Ceramics, are slender, pyramid-shaped ceramic devices that measure heat work rather than precise temperature. They are used in firing kilns to indicate the combined effect of time and temperature, with the cone's tip bending over as it approaches its specific heat work value. By monitoring the degree of bend, potters can ensure their work has received the correct amount of heat, leading to consistent results, or troubleshoot problems with their kiln.

Traditionally, 3 cones are used, 1 x of a lower cone, 1 x target cone, 1 x higher cone (guard, target, guide). This will give you more information as to how much heat-work your wares had.