Why “defects” are useful for learning

Many surface issues are not just “mistakes”: they are clues about decisions and conditions.

Crazing (fine crack lines):

• often related to glaze/body fit (thermal expansion mismatch)

• can affect water resistance and staining

Pinholes (tiny holes):

• can result from gases escaping or firing/glaze issues

• can affect surface smoothness and cleanability

Crawling (bare patches):

• glaze pulls away; could relate to surface contamination or glaze properties

Running/drips:

• glaze too fluid or too thick; can stick to kiln shelves

Figure 1 Crazing at ceramic flatware