Viscosity in salt water
Fresh-water bentonite loses much of its yield in seawater, brines and salt formations. Without a salt-tolerant viscosifier, the mud cannot lift cuttings efficiently or hold weighting material in suspension.
Industry · Oil & Gas
Drilling Fluid Clays and Additives for Oil & Gas
API 13A bentonite and attapulgite, plus organoclay for oil-based muds, supplied for viscosity, suspension and fluid-loss control in upstream drilling.
ISO 9001 certified processes
NABL-accredited lab testing
CoA, TDS & MSDS with every shipment
Export packaging worldwide
Overview
Minerals engineered for oil & gas
Drilling fluid clays and additives control how a mud carries cuttings, suspends weighting material and seals the borehole wall. Obsidian Minerals supplies the mineral side of that system for upstream oil and gas operations: bentonite and attapulgite manufactured to API 13A requirements, organoclay for oil-based and synthetic-based muds, and attapulgite-based rheology modifiers for specialised fluids.
Each mineral solves a different problem. Sodium bentonite builds viscosity and a thin, low-permeability filter cake in fresh-water muds. Attapulgite develops viscosity in seawater and brines, where bentonite loses most of its swelling capacity, which makes it a standard choice for offshore and salt-section drilling. Organoclay provides gel strength and suspension in diesel, mineral oil and synthetic base fluids, where untreated clays would not disperse or build useful structure.
We supply API 13A Section 9 and Section 11 bentonite, API 13A Section 12 attapulgite and a drilling fluid grade organoclay, with the applicable edition of the standard confirmed at order. Every lot is tested in an NABL-accredited laboratory and shipped with a Technical Data Sheet, MSDS/SDS and batch Certificate of Analysis, packed in 25 kg or 50 kg bags or 1 MT and 1.2 MT jumbo bags for rig-site handling. Samples are available for mud-lab evaluation.
Problems we help solve
Fluid loss and filter cake quality
Excess filtrate invades permeable formations, causing swelling, differential sticking and formation damage. Mud engineers need clays that build a thin, tough, low-permeability filter cake on the borehole wall.
Suspension in oil-based muds
Diesel, mineral oil and synthetic base fluids do not swell natural clays. Barite sag and poor hole cleaning follow unless an oil-dispersible gellant provides gel strength and yield point.
Specification compliance
Operators and service companies specify API 13A for clay viscosifiers. Each delivery must meet the dial reading, filtrate and residue requirements so field mud properties stay predictable.
Recommended products for Oil & Gas
Bentonite
API 13A Section 9 Drilling Grade Bentonite
Sodium bentonite produced to the API 13A Section 9 requirement of a 600 r/min dial reading of at least 30 and filtrate of no more than 15.0 cm³, for viscosity and filter cake in fresh-water muds.
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Bentonite
API 13A Section 11 OCMA-Grade Bentonite
OCMA-grade bentonite to the API 13A Section 11 requirement, including a YP/PV ratio of no more than 6, for spud and top-hole muds where this specification is called for.
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Attapulgite
API 13A Section 12 Attapulgite
Salt-tolerant attapulgite to API 13A Section 12, developing viscosity in saturated salt water for offshore, brine and salt-section drilling where bentonite yield falls away and fresh water is scarce.
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Organoclay
Organophilic Clay for Oil-Based Drilling Fluids
Organophilic clay that disperses and gels in diesel, mineral oil and synthetic base fluids, giving the yield point and gel strength needed to suspend barite and clean the hole.
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Rheology Modifier
Rheology Modifier
Attapulgite-based rheology modifier for completion, workover and specialty fluids, adding shear-thinning suspension where a non-swelling, salt-tolerant mineral thickener is preferred by the fluid designer for the well conditions.
View productOil & Gas — common questions
Which bentonite grade should I use for drilling fluids?
For most fresh-water muds, API 13A Section 9 sodium bentonite is the usual choice, because it delivers viscosity and a low-permeability filter cake. API 13A Section 11 OCMA-grade bentonite is used where that specification is called for. If the make-up water is salty, consider attapulgite instead, and confirm the choice against your mud programme.
Why use attapulgite instead of bentonite in salt water?
Bentonite relies on swelling in fresh water to build viscosity, and dissolved salts suppress that swelling. Attapulgite has needle-shaped particles that build viscosity by mechanical entanglement rather than swelling, so it performs in seawater and saturated brines. That is why API 13A Section 12 attapulgite is tested in saturated salt water and used for offshore and salt-section drilling.
Do your drilling grades meet API 13A requirements?
Our drilling bentonite and attapulgite grades are produced and tested to the API 13A Section 9, 11 and 12 requirements, including dial reading, filtrate and residue limits where they apply. The applicable edition of the standard should be confirmed at order. Results for each lot are reported on the batch Certificate of Analysis.
What packaging is available for drilling fluid clays?
Drilling grades are packed in 25 kg or 50 kg HDPE or paper bags for rig-site handling, or in 1 MT and 1.2 MT jumbo bags for bulk plants and mud stations. Custom and private-label packaging is available on request. Every shipment includes a Technical Data Sheet, MSDS/SDS and batch Certificate of Analysis.
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Talk to a oil & gas specialist
Describe your process and current material. We will recommend a grade, share the datasheet and arrange samples for trial.