| Naics index | Naics index description |
|---|---|
| 212220 | Placer silver mining and/or beneficiating |
| 212220 | Silver ore mine site development for own account |
| 212220 | Silver ores mining and/or beneficiating |
| 212220 | Sylvanite mining and/or beneficiating |
| 212220 | Telluride (gold) mining and/or beneficiating |
| 212230 | Blende (zinc) mining and/or beneficiating |
| 212230 | Calamine mining and/or beneficiating |
| 212230 | Cerussite mining and/or beneficiating |
| 212230 | Chalcocite mining and/or beneficiating |
| 212230 | Chalcopyrite mining and/or beneficiating |