History of Technology in India, Vol. I: From Antiquity to c. 1200 A.D. v1.c17.s4.t2.3

| SiO2 | 35.2-38.2 p.c | MnO2 | 1.2-2.3 |
| Fe2O3 + FeO | 43.9-48.3 | CuO | 0.7-0.9 |
| MgO | 2.4-3.6 | SO3 | 3.6-6.1 |
| Al2O3 | 5.3-7.8 | | |