Introduction to 46% Glass-Grade 325 Mesh Chrome Ore Powder
Origin of glass-grade 325 mesh chrome ore powder: South Africa
Cr₂O₃ content: ≥46%
Glass-grade chrome ore powder is mainly applied for coloring glass bottles, hence the name.
1. Chemical Indicators of Glass-Grade Chrome Ore Powder (For Glass Bottles)
| Test Item | Standard Requirement | Typical Measured Value | Function in Glass Production |
|---|---|---|---|
| Cr₂O₃ | ≥46.0% | 46.3~46.8% | Produces stable emerald green and olive green coloration |
| Total Iron (FeO) | ≤26.5% | Within 26.0% | Low iron content prevents yellowing and grey spots, ensures consistent color difference of finished products |
| Cr/Fe Ratio | ≥1.55:1 | 1.58:1 | Mandatory index for high-end green glass, ensures uniform UV shielding performance |
| SiO₂ | ≤1.0% | 0.92% | Excessive silicon impurities cause air bubbles and pits on bottle surfaces |
| Al₂O₃ | ≤15.5% | 13.5% | Stabilizes the glass melting system |
| CaO | ≤0.30% | 0.11% | Eliminates stone and black speck defects |
| TiO₂ | ≤1.0% | 0.60% | Prevents dark and turbid glass appearance |
| P, S | ≤0.003% | Trace amounts | Avoids foaming and streaking in melting furnaces |
2. Properties of Glass-Grade 325 Mesh Chrome Ore Powder
- Particle size: 325 mesh, sieve passing rate ≥95%, particle size ≤45μm, superfine without coarse particles
- Appearance: Dark brown-black powder
- Moisture: ≤0.1%, dried treatment, no dusting or caking during feeding
- True density: 4.1~4.5 g/cm³; bulk density: 2.5~3.0 g/cm³
- Melting point: 2180℃, compatible with glass melting furnaces operating at 1450~1550℃
- Production process: South African raw ore → water washing for impurity removal → ultrafine grinding → fine screening → drying to finished product
3. Core Application Scenarios (Glass Industry)
Food UV-blocking glass bottles (Main Application)
Beer bottles, red wine bottles, fruit wine bottles, essential oil bottles, green bottles for sauces and condiments. The dark green tint blocks ultraviolet rays and extends the shelf life of beverages. It replaces high-priced synthetic chromium oxide green and cuts coloring costs by over 35%.
Industrial green glass
Daily chemical cream bottles, light-proof containers for chemical reagents, green architectural flat glass.
Extended auxiliary application
Minor usage for green coloring of ceramic glazes.
Do not mix with high-iron ore powder (Zimbabwe ore), which will cause yellow discoloration and scrapping of glass bottles.
4. Product Advantages
- Water washing process removes sediment, resulting in minimal air bubbles, stones and black specks during melting, greatly reducing glass rejection rate;
- 325 mesh superfine particles disperse evenly in glass batch materials, delivering consistent color across all batches of bottles;
- Natural trivalent chromium does not generate toxic hexavalent chromium under high-temperature melting, complying with safety standards for food contact containers;
- Stable tinting strength; slight fluctuations in furnace temperature will not alter the green shade of glass, delivering reliable production control.
5. Packaging Specifications
- Bulk cargo: 1000kg jumbo bags
- Small trial orders: 25kg woven bags, 40 bags per ton
- Free 1–2kg samples are available for color matching tests at glass factories