barite - Schlumberger Oilfield GlossaryA dense mineral comprising barium sulfate [BaSO4]. Commonly used as a weighting agent for all types of drilling fluids, barites are mined in many areas worldwide and shipped as ore to grinding plants in strategic locations, where API specifies grinding to a particle size of 3 to74 microns. Pure barium sulfate has a specific.barite powder size,Barite Ultra Fine TDS - Clear Solutions International LtdBarite Ultra Fine weighting media is a high quality, drilling grade barite (barium sulphate) used to increase the density of drilling fluids. It is ground to a finer particle size than regular. API-‐spec barite. This product has been developed to enable drilling fluids to be run with lower viscosity and hence lower ECD values and.