Bentonite — Sodium & Calcium, Multi-Grade
Bulk and bagged bentonite from verified Chinese mining and processing sources. API 13A / OCMA / GB/T 20973 compliant grades available. FOB / CIF from major Chinese ports.
Supplied to oilfield drilling contractors, civil engineering firms, foundries, iron ore pelletizing plants, and water treatment operators across the Middle East, Southeast Asia, Africa, and the Americas. Every shipment third-party tested — COA and MTC included as standard.
Select the Right Grade for Your Application
Miningsun supplies bentonite across four primary industrial grades, each processed and tested to meet the relevant international specification. Mixed or custom grade inquiries welcome.
API / OCMA Grade
Sodium bentonite meeting API 13A Section 9 (API Grade) and Section 11 (OCMA Grade). High yield, high viscosity, excellent fluid-loss control for water-based drilling muds.
- Oil & gas well drilling
- Water well & HDD drilling
- Geotechnical boreholes
- Borehole sealing & grouting
Civil & GCL Grade
High-swelling sodium bentonite for waterproofing, containment, and barrier applications. Meets requirements for geosynthetic clay liners, slurry walls, and pond sealing.
- Geosynthetic clay liners (GCL)
- Diaphragm walls & pile boring
- Landfill & reservoir lining
- Horizontal directional drilling (HDD)
Foundry & Pelletizing Grade
Thermally stable sodium bentonite with high green strength for metal casting mold sand. Also used as a binder in iron ore pelletizing to produce blast-furnace feed pellets.
- Iron, steel & non-ferrous foundry
- Iron ore pelletizing (binder)
- Green sand mold preparation
- Ceramic & construction binders
Exceptional Swelling & Absorption
Sodium bentonite swells up to 15× its dry volume in water — forming impermeable gels essential for drilling mud performance, wellbore sealing, and environmental containment.
API 13A / OCMA Certified
Drilling grade bentonite tested and compliant with API 13A Section 9 and Section 11 (OCMA) specifications. Yield ≥ 90 bbl/ton, fluid loss ≤ 15 ml/30 min. COA per shipment.
Verified Chinese Source, Stable Supply
China holds the world's second-largest bentonite reserves. Miningsun sources from established inner Mongolia and Xinjiang mines with consistent montmorillonite content and year-round availability.
High Montmorillonite Content
Our sodium bentonite carries ≥ 75% montmorillonite — the active mineral responsible for swelling, viscosity, and cation exchange performance. Lower-grade material is rejected at source.
Flexible Mesh Size & Packaging
Supplied in powder (200 mesh) or granular form. 25 kg PP bags, 1 MT / 1.5 MT jumbo bags (FIBC), or bulk vessel loading. Custom mesh size and private-label bagging available.
Full Export Documentation
COA, MTC, CO, MSDS, and third-party inspection (SGS / BV / CIQ) available. All paperwork handled by our experienced export team in English and Chinese.
Specifications by Grade
Key parameters for our primary export grades. Drilling grade is tested per API 13A; Civil/GCL grade per EN 13242 and project-specific requirements; Foundry grade per ISO 1872-2. Custom specifications available on request.
| Parameter | API Grade (Sec. 9) | OCMA Grade (Sec. 11) | Civil / GCL Grade | Foundry Grade |
|---|---|---|---|---|
| Montmorillonite Content (min) | ≥ 75% | ≥ 65% | ≥ 70% | ≥ 70% |
| Viscometer Reading @ 600 rpm (min) | ≥ 30 cp | ≥ 25 cp | — | — |
| Yield (min, bbl/ton) | ≥ 90 | ≥ 70 | — | — |
| Fluid Loss (max, ml/30 min) | ≤ 15 | ≤ 22.5 | — | — |
| Free Swelling Index (min, ml/2 g) | ≥ 24 | ≥ 16 | ≥ 24 | — |
| Moisture Content (max) | ≤ 10% | ≤ 13% | ≤ 12% | ≤ 10% |
| Sand Content (max) | ≤ 2.5% | ≤ 4.0% | ≤ 4.0% | ≤ 3.0% |
| pH (2% suspension) | 8.5 – 10.5 | 8.0 – 11.0 | 8.0 – 10.5 | 8.0 – 10.0 |
| Particle Size (mesh) | 200 mesh | 200 mesh | 60–200 mesh | 100–200 mesh |
* Typical values from production. Batch-specific COA issued with every shipment. Custom grades and mesh sizes available on request.
Where Our Customers Use Bentonite
From oil well drilling in the Gulf to landfill liners in Europe — bentonite's unique swelling, binding, and absorption properties make it indispensable across multiple industries.
Oil & Gas Well Drilling
API / OCMA grade drilling mud for wellbore stabilization, cuttings transport, and fluid-loss control in water-based mud systems.
Civil Engineering & Tunneling
Slurry walls, diaphragm walls, tunnel boring, pile boring. Bentonite slurry provides borehole stability and lubrication.
Geosynthetic Clay Liners (GCL)
High-swelling sodium bentonite needle-punched or glued between geotextile layers for landfill, pond, and reservoir containment.
Foundry Sand Bonding
Binder in green sand mold preparation for iron, steel, and non-ferrous casting. Improves green strength and thermal stability.
Iron Ore Pelletizing
Binder for iron ore fines conversion into blast-furnace pellets. Low addition rates (0.5–1.5%) with excellent balling efficiency.
Water Treatment & Environmental
Wastewater clarification, heavy metal adsorption, lagoon sealing, and contaminated site remediation.
Packaging, Ports & Payment
Flexible packaging and incoterms to match your application, discharge facilities, and project scale.
Packaging Options
- 25 kg PP woven bags, palletized & shrink-wrapped
- 50 kg PP bags available on request
- 1,000 kg / 1,500 kg jumbo bags (FIBC) with PE liner
- Bulk loading into vessel holds (500+ MT)
- 20' / 40' container stuffing available
- Custom private-label bagging on request
Loading Ports
- Tianjin / Xingang Port (primary)
- Qingdao Port
- Shanghai Port
- Lianyungang Port
- Bulk vessels and container shipments arranged
Payment Terms
- 30% T/T deposit, 70% balance against B/L copy
- L/C at sight (irrevocable, from prime banks)
- D/P, D/A negotiable for established buyers
- Trial orders accepted to build long-term relationships
Documentation Provided
- Commercial Invoice & Packing List
- Bill of Lading (B/L)
- Certificate of Origin (CO / Form A / FORM E)
- Mill Test Certificate (MTC) & COA per shipment
- SGS / BV / CIQ third-party inspection on request
Direct-Source Supplier. Multi-Grade Capability.
China is the world's second-largest bentonite producer, with major deposits in Inner Mongolia, Xinjiang, and Liaoning. Miningsun sources directly from established mining operations and processing facilities — delivering consistent, specification-grade bentonite at competitive export pricing.
- Direct mine sourcing — long-term supply agreements with established Chinese bentonite mines and processors
- Multi-grade capability — API drilling, OCMA, civil/GCL, foundry, and feed-additive grades from a single supplier
- Third-party tested — API 13A / GB/T 20973 compliance with COA on every shipment
- Custom mesh sizes — 60 to 325 mesh powder or granular forms to match your process requirements
- Stable pricing — quarterly fixed-price contracts available for repeat buyers and volume commitments
- Reliable lead times — 15–25 days from PO to vessel loading, consistently
- Full export documentation — CO, MTC, MSDS, SGS/BV inspection, fumigation as required
- Responsive sales team — quotes within 24 hours, English / Chinese supported
Technical & Compliance Documents
Available to qualified buyers upon request — please specify grade, mesh size, and estimated annual volume when reaching out.
Request a Quote for Bentonite
Tell us your required grade, mesh size, annual volume, destination port, and packaging preference — we'll respond with a competitive FOB/CIF price within 24 hours.
Get a Price Or email us directly: info@miningsun.com · WhatsApp: +1 814 515 0096