Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7544231 | Recovery of platinum group metals | Grenvil Marquis Dunn, John Derek Lewins | 2009-06-09 |
| 7282080 | Process for extracting platinum group metals | John Derek Lewins | 2007-10-16 |