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calcium mud

1. n. [Drilling Fluids]
A class of water-base drilling fluid that utilize dissolved Ca+2 as a component. Examples are lime mud, gyp mud and calcium chloride [CaCl2] mud. The latter is rarely used, but is based on solutions of CaCl2 that, in high concentration, can impart density up to 11.6 lbm/gal (1.39 g/cm3) and has been touted as providing shale inhibition.