Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4879388 | Extraction of metal values | David Stewart, Anthony J. Nelson | 1989-11-07 |
| 4822880 | Process for the extraction of metal values and novel metal extractants | David P. Devonald, Anthony J. Nelson, David Stewart | 1989-04-18 |