| because of that process | 8 | cause |
| in variable amounts | 7 | other |
| always | 6 | temporal |
| opal → contain → water | 30 |
| opal → have → high water content | 9 |
| opal → contain → up to 20% water | 5 |
| opal → contain → some water | 3 |
| negative | neutral | positive |
| 0.269 | 0.625 | 0.106 |
| Raw frequency | 47 |
| Normalized frequency | 0.796 |
| Modifier score | 0.900 |
| Perplexity | 286.902 |