M-I BAR Barite | SLB



Schlumberger Oilfield Services
Schlumberger Oilfield Services

M-I BAR barite is a high-quality, drilling-grade barite (barium sulfate) used to increase the density of drilling fluids.

This high-specific-gravity mineral is the most widely used weight barite, has application in all drilling fluid systems, and meets all API specifications for barite.

Typical Physical Properties
Physical appearance Powder of various light colors: gray, pink, tan
Bulk density 107–135 lb/ft3 [1,714–2,162 kg/m3]

API Specifications
Density Min. 4.20 g/cm3
Soluble hardness (as calcium) Max. 250 mg/kg
Particles >75 um (wet screen) Max. 3 wt%
Particles <6 um (sedimentation) Max. 30 wt%


M-I BAR barite can be used to increase the density of any mud system. Mud weights up to 20 lbm/galUS [2.40 sg] can be achieved in most drilling fluids while still maintaining good rheological properties. M-I BAR barite is also excellent in formulating special kill fluids and barite plugs that often reach 22 lbm/galUS [2.64 sg] for well control procedures.

An increase in volume of approximately 1.4 bbl/tonUS (0.25 m3/tonUK) can be expected from M-I BAR barite additions. Density increases can require water or base liquid dilution sufficient to wet the surfaces of the added barite adequately.


  • Essentially chemically inert and insoluble, functions only in a physical manner
  • Does not react with other drilling fluid additives or interfere with their function
  • Minimally abrasive

Toxicity and handling

Bioassay information is available upon request. Handle as an industrial chemical, wearing protective equipment and observing the precautions described in the barite safety data sheet.

Packaging and storage

M-I BAR barite is packaged in 100-lbm [45.4-kg] multiwall paper sacks; 40-kg sacks; and big bags available in bulk.

Store in a dry, well-ventilated area. Keep container closed. Store away from incompatibles. Follow safe warehousing practices regarding palletizing, banding, shrink-wrapping, and stacking.