How bad can efflorescence on terra cotta be?

Saturday 12th October 2013

Like this! This terra cotta clay matures to good strength around 1950F. Notice how the insight-live.com/glossary/254">soluble salts have concentrated on the outer and most visible surface. The piece was dried upside down so, of course, all the water had to escape through that route. A complicating factor is how handling of the piece at the leather hard stage has made it even more unsightly. This problem is common in many terra cotta materials but can also surface in others. A tiny addition of barium carbonate can precipitate the salts inside the clay matrix so they do not come to the surface on drying.

Pages that reference this post in the Digitalfire Reference Library:

Mexican terra cotta bisque tile is "complicted", The magic of a small barium carbonate addition to a clay body, How bad can efflorescence be in natural clays? This bad!, Barium Carbonate in Clay Bodies, Soluble Salts, Terra Cotta, Sulfates, Efflorescence

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.