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unweighted mud

1. n. [Drilling Fluids]
A mud that contains no commercial weighting material. Native-solids muds are unweighted muds, containing no barite. More solids-control techniques are available for unweighted muds than for weighted muds. In fact, dilution of unweighted muds is highly economical.
Synonyms: native-solids mud
Antonyms: weighted mud