Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5372630 | Direct sulphidization fuming of zinc | Rodney L. Leonard, John G. Whellock, Richard S. Celmer | 1994-12-13 |
| 4274868 | Recovery of tin from ores or other materials | William T. Denholm | 1981-06-23 |