Xanthan gum — the biopolymer the industry calls XC or XCD polymer — is the strongest suspension viscosifier used in water-based drilling fluid. Ironstone supplies drilling-grade xanthan in standard and dispersible grades, with a certificate of analysis for every batch.
XC polymer is xanthan gum: a high-molecular-weight polysaccharide made by fermentation. Its value in drilling fluid is its strongly shear-thinning behavior — thin under the high shear inside the drill string and at the bit (so pump pressure stays manageable), and thick where the fluid moves slowly in the annulus and when the pumps stop. That low-shear thickness is what carries cuttings up the hole and holds barite and cuttings in suspension between connections. It is the first-choice viscosifier for HDD and low-solids fluids.
They are the same base biopolymer; the difference is qualification and treatment, not the molecule. Food grade is certified for purity and food safety. Drilling grade is controlled for mud performance — viscometer readings in salt brine, and particle treatment so it disperses in the field without lumping — and is tested against oilfield methods. Food grade is therefore not a specification substitute: it is qualified for a different job.
| Parameter | Value | Basis |
|---|---|---|
| Appearance | Cream free-flowing powder | Manufacturer COA |
| Starch or starch derivatives | Absent | Manufacturer COA (API 13A method) |
| Moisture mass fraction | ≤ 13% | Manufacturer COA |
| Particle size | 40 / 80 mesh (drilling) | Manufacturer COA |
| pH (1% solution) | 6.0 – 8.0 | Manufacturer COA |
| Viscosity | ≥ 1200 cP in 1% KCl brine | Manufacturer COA |
| Ash | ≤ 15% | Manufacturer COA |
| Low-shear viscometer readings | Reported on the certificate of analysis | Manufacturer COA |
Ironstone does not operate a laboratory. Every figure in this table comes from the manufacturer’s certificate of analysis or data sheet, and the certificate for your batch states the exact figures. Independent testing or inspection before loading can be arranged on request.
We buy to the API Spec 13A requirements for xanthan gum, and we write those requirements into the purchase contract rather than accepting a supplier’s typical values. The distinction matters when a batch is disputed. Typical values describe what production usually does. The guaranteed specification is the figure you can enforce against a certificate of analysis.
A data sheet can guarantee a limit looser than the standard it claims to meet, and a moisture ceiling above the API maximum is the common example, even where actual production passes comfortably. So read the guaranteed limits on a data sheet rather than the typical figures, and where a guarantee is wider than the standard allows, require the order to state the standard’s limit.
One further check applies to any viscometer figure you are comparing between offers: confirm the test conditions. The standard’s readings are taken on a defined laboratory solution using a specified torsion spring and rotor, so a reading taken any other way is not comparable, and a reading taken with a different spring can make material that meets the specification appear to fail.
Xanthan needs shear and controlled addition. Untreated powder hydrates fast at the particle surface, so if it is dumped into water faster than it disperses it forms “fish-eyes” — lumps whose outer surface has gelled and sealed dry powder inside. Add it slowly through a hopper or high-shear mixer, or use the dispersible grade where mixing is manual or done in the field. Dosage is set to the suspension and hole-cleaning target by pilot test; we include the technical data sheet with guidance when we quote.
We quote rather than publish a list price. Polymer and freight prices both move, so a published number is out of date before you read it. Send your volume, your grade and your delivery port by WhatsApp or email. We reply within one working day, and we hold the price we quote for seven days against that volume and that port.
What we take responsibility for.Our purchase order states the specification on this page, not the supplier’s typical values. Before we release payment to the factory we require a certificate of analysis for your batch, and that certificate must include the starch test result. If it fails the specification we reject the batch: that is our problem, not yours. Independent inspection before loading is available on request, at cost.