Coarse feldspar aggregates from the same Limpopo Province pegmatite ore body as our micronised range. Four grades from glass-grade fine aggregate to 25mm coarse material. Low iron Fe₂O₃ <0.3%.
View Mineral Samples ↓Screened Feldspar Aggregates are produced from the same long-established Limpopo Province pegmatite ore body as the Microbrite® micronised range — ensuring consistent chemistry, predictable alkali content and low iron (Fe₂O₃ <0.3% for GG Grade).
Four grades serve distinct applications from glassmaking and ceramic body use through to abrasive, surface-treatment and coarse aggregate applications. All grades are screened and classified at the Limpopo Province mine site, with VSI processing available for the Feldspar-6 grade to reduce mica content and improve particle shape.
What is VSI processing? VSI stands for Vertical Shaft Impactor, a type of crusher in which a high-speed rotor throws the feldspar against a hard anvil or rock lining. The particles break along their natural fracture lines, giving a more cube-shaped (cuboid) particle rather than flat or elongated flakes. Cuboid particles pack together more tightly, and soft, platy mica tends to break down into fines that can be screened out, lowering the mica content of the finished grade.
Four grades covering the full coarse feldspar aggregate range — glass grade fine to coarse decorative aggregate.
| Grade | Size Range | Fe₂O₃ | Key Feature | Primary Applications |
|---|---|---|---|---|
| GG (Glass Grade) | <1180μm | <0.3% | Low-iron fine aggregate | Glass manufacture, glassmaking batch, ceramic frits |
| Feldspar-3 | 0–3mm | Standard | Fine aggregate | Ceramic body, tile body, mortar aggregate |
| Feldspar-6 | 0–6mm | Standard | VSI-processed, low mica | Construction aggregate, abrasive and surface treatment |
| Feldspar-15 | 6–25mm (D50 15mm) | Standard | Coarse aggregate | Decorative aggregate, landscaping, coarse fill |
Grade specifications are typical values. Contact us for detailed TDS and CoA per grade.
Screened Feldspar GG (Glass Grade) from Limpopo Province, South Africa. Low-iron fine aggregate for glass manufacture and ceramic frits.
Glass Grade fine aggregate, Fe₂O₃ <0.3% — an alumina and alkali source for glass batch, suited to coloured glass such as amber.
