| Property | Specification |
| Appearance | Brown, gray, or dark-colored rock or powder |
| Form | Lumps, granules, or powdered |
| Bulk Density | 1.2 – 1.5 g/cm³ |
| Specific Gravity | 2.6 – 3.2 |
| Hardness (Mohs Scale) | 5 – 6 |
| Moisture Content | ≤ 2% |
| Particle Size | As required (commonly 100–150 mesh) |
| P₂O₅ (Phosphorus Pentoxide) | 26% – 34% (depending on grade) |
| Calcium Oxide (CaO) | 45% – 50% |
| Fluorine (F) | 2% – 4% |
| Iron Oxide (Fe₂O₃) | ≤ 2% |
| Color | Grayish, brownish, or black |
| Odor | Odorless |
| Solubility | Insoluble in water; soluble in acids |
