Bentonite is used during drilling and tunneling fluids to lubricate and cool cutting tools, remove cuttings and help prevent blowouts. It is a common component in drilling mud used to curtail drilling fluid invasion through its propensity to aid in the formation of mud cakes. Bentonite API Grade is used to increase viscosity and reduce fluidâ??loss in waterâ??base drilling fluids. It is a costâ??effective means of achieving viscosity, fluidâ??loss control, and filterâ??cake quality in freshwater and seawater mud.