• A clay composed principally of minerals in the montmorillonite group and characterized by high absorption and very large volume change with wetting or drying.


  • a type of clay that is used in fining to clarify wines, usually white wines. The clay is stirred into a wine, and as it settles to the bottom it absorbs any suspended particles and excess yeast that could otherwise cloud the wine. The clay is then filtered or racked off, taking the yeast protein with it.