Print, Photographic

Black and white photographic print mounted on fabric depicting glazing equipment at the Champion Spark Plug Co.
Caption reads: Photograph 13
After the blanks are shaped into cores they are glazed. Glaze is a ceramic mixture, very finely ground, and so compounded that it will melt to a glass on the surface of the core when coated in a layer on the unfired core and then fired to the temperature at which porcelain body matures or vitrifies. The glaze makes a smooth surface which is easily cleaned. The porcelain itself is vitreous, however, and absolutely non-absorbent.