Bentonite Granules Types Explained — A Buyer's Guide to Every Grade and Which to Order

Introduction

"Bentonite granules" is not one product — it is a family of grades, each engineered for a different job. Ordering the wrong one wastes money and underperforms. This buyer's guide maps the full bentonite granule range, explains what each grade is for, and gives a simple decision framework so you order the right grade the first time.

The Two Big Families: Industrial vs Agricultural

Most bentonite granules fall into one of two broad uses:

• Industrial grades — chosen for swelling, binding, sealing, and absorption: drilling, foundry, civil, pelletizing, and spill control.
• Agricultural grades — chosen for soil conditioning, fertilizer binding/carrying, and biostimulant delivery.

Some grades serve both. The framework below sorts them out.

Industrial Ball Granules

Red Ball Granules High swell index (24–30 ml/2g), >85% montmorillonite, 8–12% iron oxide. The high-yield drilling and civil grade; iron adds micronutrient value in agriculture. See red ball for drilling.

Black Ball Granules Highest montmorillonite (>88%) with defined CEC (60–90 meq/100g). Favoured for high-performance foundry green sand and exacting binding/sealing. Compare the two in black ball vs red ball.

Bentonite Absorbent Granules Engineered for absorption (≈5× own weight, ultra-low dust) for oil and chemical spill cleanup and workshop safety — detailed in our .