Premium potash feldspar filler from established Limpopo Province pegmatite deposits. Low iron. High brightness. Consistent chemistry, every batch.
View Mineral Samples ↓Microbrite® is produced from consistent, long-established Limpopo Province pegmatite deposits — mined and processed by a production partner with over 50 years of operational heritage. Every batch of Microbrite® comes from a single, documented source, with published chemistry ranges, verifiable origin and full documentation.
Buyers currently formulating with European feldspar grades will find Microbrite® a technically credible, cost-competitive alternative backed by responsible mineral supply — documented origin and traceability from mine to UK delivery.
Typical chemical composition from Limpopo Province pegmatite. Mean values — not a specification.
| Compound | Range / Mean Value |
|---|---|
| SiO₂ | 70.00–75.00% |
| Al₂O₃ | 15.50–18.00% |
| Fe₂O₃ | 0.10–0.20% |
| K₂O / Na₂O | 9.00–11.00% |
| MgO | < 0.10% |
| TiO₂ | < 0.01% |
| CaO | < 0.50% |
| P₂O₅ | < 0.05% |
| LOI | < 0.50% |
SiO₂ is chemically bound within the pegmatite. Typical values. Contact us for specification confirmation.
All grades are milled and classified, with particle size quality-controlled by wet sieve analysis. Laser-diffraction PSD data available on request.
| Property | Unit | Microbrite® 2 | Microbrite® 5 | Microbrite® 10 | Microbrite® 15 |
|---|---|---|---|---|---|
| % Retained @ 25μm | % weight | < 2.0 | N/A | N/A | N/A |
| % Retained @ 63μm | % weight | N/A | < 1.0 | N/A | N/A |
| % Retained @ 75μm | % weight | N/A | N/A | < 1.0 | N/A |
| % Retained @ 106μm | % weight | N/A | N/A | N/A | < 2.0 ** |
| Average Particle Size d50 | μm | 6.8 | 12.7 | 20.1 | 27.6 |
| Oil Absorption | % | 25 | 22 | 21 | 17 |
| Reflectance (Opacity Reflectometer) | % | 93 | 92 | 92 | 92 |
| Bulk Density (As Packed) | kg/litre | 0.70 | 0.85 | 0.90 | 0.93 |
| Specific Gravity | kg/litre | 2.59 | 2.59 | 2.59 | 2.59 |
| Hardness | Mohs | 6 | 6 | 6 | 6 |
| Melting Point | °C | >1100 | >1100 | >1100 | >1100 |
| Packaging | — | 25kg & 1000kg | 25kg & 1000kg | 25kg & 1000kg | 25kg & 1000kg |
Mean values. These do not represent a specification. ** Quality controlled by means of wet sieve analysis. d50 range: 6.8–27.6μm across all four grades.
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Microbrite® potash feldspar from Limpopo Province, South Africa. Fine micronised grades for consistent dispersion in paints, coatings, ceramics and plastics applications.
Finest grade with d50 6.8μm. Delivers maximum surface area and dispersibility in fine-finish paints, coatings and sealants where a fine particle size is required.
Coarser grade with d50 27.6μm and the lowest oil absorption in the range (17%). Suited to industrial coatings, sealants and plasters where filler loading and cost-performance matter.
Contact our technical team to receive the complete Microbrite® TDS, SDS and Certificate of Analysis. Grade selection guidance and application support available.