Which tool is used in the firing of ceramics?

In ceramic firing, a pyrometer is essential as it measures the temperature inside the kiln. The firing process requires precise temperature control to ensure that the clay reaches the necessary heat levels for proper vitrification, which transforms the raw clay into ceramics. Pyrometers can be digital or analog and provide real-time readings that inform the artist when to make adjustments, ensuring consistent results in their ceramics.

Other tools, like a brush, may be useful for applying glazes, while a ruler is typically used for measuring dimensions in the initial stages of forming or modeling clay. Canvas can serve as a surface for working or drying clay pieces but does not play a role in the actual firing process. Thus, the pyrometer stands out as the tool directly related to the critical firing stage in ceramics.