The magic of a small barium carbonate addition to a clay body

Thursday 2nd January 2014

Two bisqued insight-live.com/glossary/88">terracotta mugs demonstrate efflorescence. The clay on the right has 0.35% added barium carbonate (it precipitated the natural soluble salts dissolved in the clay and prevented them from coming to the surface with the water and being left there during drying). The process is called efflorescence and is the bane of the brick industry. The one on the left is the natural clay. The unsightly appearance is fingerprints from handling the piece in the leather-hard state, the salts have concentrated in these areas (the other piece was also handled).

Pages that reference this post in the Digitalfire Reference Library:

Barium Carbonate, The Use of Barium in Clay Bodies, Efflorescence, Soluble Salts, Brick Making

This post is one of thousands found in the Digitalfire Reference Database. Most are part of a timeline maintained by Tony Hansen. You can search that timeline on the home page of digitalfire.com.