Industrial Minerals
What it is
Talc is a hydrated magnesium silicate with a platy crystal habit and a Mohs hardness of 1, the softest mineral there is. Those plates are what make it useful: they lie flat in a film or a melt, which stiffens plastics, reduces permeability in coatings and gives paper a smooth surface without abrading the machine.
Why buyers specify it
- Platy particles reinforce without the hardness that wears out extruder screws and mixing blades.
- Low oil absorption compared with clays, so a formulation takes more filler before it thickens.
- Naturally hydrophobic, which helps in pitch control on a paper machine and in anti-stick duties.
- Chemically inert and stable to roughly 900 °C before it begins to lose its structural water.
Grades we supply
Grade names are ours; the fineness and the duty are what you match against your current material.
| Grade | Fineness | Typical D50 | Usually bought for |
|---|---|---|---|
| XT-200 | 200 mesh (75 µm) | 18–25 µm | Rubber, dusting, economy fillers |
| XT-325 | 325 mesh (45 µm) | 10–15 µm | Paint, putty, adhesives |
| XT-500 | 500 mesh (25 µm) | 7–10 µm | Polypropylene compounds, sealants |
| XT-800 | 800 mesh (15 µm) | 4–6 µm | Masterbatch, automotive PP |
| XT-1250 | 1250 mesh (10 µm) | 2–4 µm | High-gloss coatings, films, technical ceramics |
Other finenesses and surface treatments are available against a firm enquiry. If you are switching from another supplier, send their data sheet and we will match the curve rather than the mesh number.
Typical analysis
Chemistry
| Component | Typical range | Note |
|---|---|---|
| SiO2 | 58 – 62 % | Theoretical talc is 63.4 % |
| MgO | 28 – 32 % | Theoretical 31.9 % |
| CaO | 0.3 – 2.5 % | Rises with dolomitic talc |
| Al2O3 | 0.3 – 2.0 % | From associated chlorite |
| Fe2O3 | 0.2 – 1.2 % | Lower is whiter |
| Loss on ignition | 5.0 – 7.0 % | Structural water, driven off above 900 °C |
Physical properties
| Property | Typical range | Method basis |
|---|---|---|
| ISO brightness | 85 – 94 % | Elrepho, dry powder |
| Whiteness (Hunter L) | 88 – 95 | — |
| Oil absorption | 28 – 45 g/100 g | Spatula rub-out |
| Specific gravity | 2.7 – 2.8 | — |
| pH (10 % slurry) | 8.5 – 9.5 | — |
| Moisture as packed | ≤ 0.5 % | 2 h at 105 °C |
| Mohs hardness | 1 | — |
These are typical ranges for talc, not a specification. The values that govern your order are the ones measured on your lot and printed on its mill test certificate. Ask for a sample and the certificate that goes with it before you commit a production trial.
Where it is used
Talc is not one product sold 7 ways — it is 7 different conversations about the same mineral. We supply it into plastics & masterbatch, paint & coatings, paper & board, rubber, ceramics & sanitaryware, adhesives & sealants and detergents & soaps, and in each of those the grade that works is chosen for a different reason: fineness in one, brightness in another, oil absorption or purity in the next.
Each industry below has its own page on this site, written for the people who formulate in it rather than for a general reader. If you work in one of them, start there — it will tell you which talc grade we would quote for your application and what we need to know before quoting it.
- Plastics & Masterbatch — Polypropylene stiffening, heat deflection and dimensional stability; 10–40 % loading.
- Paint & Coatings — Extender pigment for flatting, anti-settling and burnish resistance.
- Paper & Board — Filler and pitch-control agent; improves smoothness and ink receptivity.
- Rubber — Semi-reinforcing filler and anti-tack dusting agent.
- Ceramics & Sanitaryware — Flux for low thermal expansion bodies and steatite insulators.
- Adhesives & Sealants — Thixotropy and volume in sealants and construction mastics.
- Detergents & Soaps — Filler and mild abrasive in powders and scouring products.
Asbestos. Talc and asbestiform amphiboles can occur in the same geology, so the question every serious buyer asks first is how the ore is selected and tested. We buy from deposits worked for industrial talc, and lots destined for the United States are tested by polarised light microscopy and transmission electron microscopy, with the certificate travelling with the shipment. If your application is cosmetic or pharmaceutical, say so on the enquiry — that is a separate supply chain with separate documentation, not a grade change.
Substitution. If you are replacing another supplier's talc, send us their data sheet rather than just the mesh number. Two 325-mesh talcs with different top cuts and oil absorptions behave very differently in a paint, and matching the curve matters more than matching the headline figure.
Packing
| Pack | Detail | Suits |
|---|---|---|
| 25 kg paper or PP bag | Palletised 40 bags per pallet, stretch-wrapped | Powders |
| 50 lb bag | US-standard weight where the plant prefers it | Powders |
| 1,000 kg / 1 MT jumbo bag | Four-loop FIBC with discharge spout | Powders, sand, granules |
| Bulk | Pneumatic tanker or loose in container, where volume justifies it | Sand, granules, lump |
Private-label bags with your own artwork are available from one container. How private label works.
Documents with every shipment
- Mill test certificate for the lot, with the measured values, not the range
- Certificate of analysis signed by the processing plant
- Safety data sheet in the US 16-section GHS format
- Certificate of origin and the commercial invoice and packing list
- Asbestos test report where the mineral and the application call for one
Related minerals
Need a price on talc?
Send the grade, the tonnage and the delivery ZIP code. Quote and free sample back within one business day.