| Test No. | Recipe | % | Added Colorant |
| Test 14 | Frit (WZBF) | 20% | 8 g P4188.5 |
| Flint | 80% | ||
| Test 15 | Frit (WZBF) | 10% | 8 g P4182.5 |
| Silica | 90% | ||
| Test 16 | Frit (WZBF) | 20% | 8 g P4136.5 |
| Potash Feldspar | 80% |