Random triples
| Subject | Object |
|---|---|
| gptkb:Schneeberg_mining_region | 16th century |
| gptkb:Lead_Belt_region | early 20th century |
| gptkb:Derbyshire_coalfield | 19th century |
| gptkb:Durham_coalfield | 19th century |
| gptkb:Leadville_Mining_District | 1880s |
| gptkb:Southeast_Missouri_Mining_and_Milling_Division | 20th century |
| gptkb:Warwickshire_coalfield | 19th century |