A term used to specify the quality of a clay according to the number of barrels of 30-cp viscosity mud that one ton of the clay would produce. Although seldom used today, clays were classified as high-, medium- or low-yield bentonites. A "good" bentonite produced at least 85 bbl of mud per ton. High-yield clays produced 30 to 50 bbl/ton, and low-yield clays produced 15 to 30 bbl/ton. (Note that yield and yield point are not related terms.)

Related Terms:

low-yield clay
viscosity