| mostly | 5 | degree |
| at official government heritage | 5 | location |
| around 1850 | 2 | temporal |
| opal → be found in → australia | 18 |
| opal → be discovered in → australia | 16 |
| opal → be found in → queensland | 3 |
| opal → be discovered in → queensland | 3 |
| negative | neutral | positive |
| 0.028 | 0.689 | 0.282 |
| Raw frequency | 40 |
| Normalized frequency | 0.750 |
| Modifier score | 0.860 |
| Perplexity | 63.703 |