Organophilic clay is the viscosifier and suspension agent of oil-based and synthetic-based drilling fluid — the core rheology product of an invert emulsion. Ironstone supplies OBM-grade organophilic clay with a certificate of analysis for every batch.
Ordinary bentonite needs water to work and does nothing in oil. Organophilic clay is bentonite — or hectorite for high-temperature service — whose surface has been treated with fatty quaternary amine compounds so it disperses in oil instead of water. Once dispersed with enough shear, the treated clay platelets build the gel structure that gives the invert its viscosity and its ability to suspend barite and cuttings. It is usually the core rheology product of the whole formulation.
| Parameter | Typical value | Basis |
|---|---|---|
| Base mineral | Amine-treated bentonite (hectorite for high temperature) | — |
| Appearance | Off-white to tan fine powder | Visual |
| Moisture | ≤ 3.5% | Oven, 105 °C |
| Fineness | ≥ 98% through 150 mesh | Sieve |
| Viscosity / yield | ≥ 35 cP at 600 r/min in 3% mineral oil | Fann in reference oil |
| Specific gravity | About 1.7 | — |
| Bulk density | 0.40 – 0.60 g/cm³ | — |
Typical drilling-grade values. Yield is only meaningful with the reference oil and loading stated, so the certificate of analysis reports the test oil and the exact figures for each batch.
The right grade depends on your base fluid and temperature. Bentonite-based organoclays cover most diesel and mineral-oil systems; hectorite-based grades keep performing at higher temperatures. Because performance is set by yield in your base fluid, a candidate proven in one oil is not automatically proven in another — our BENTONE 38 / VG-69 equivalents page sets out what to test before switching.
Indicative CIF price on request; indicative FOB ranges appear in the monthly Price Letter. For a firm price, send your base fluid, volume, and port on WhatsApp.