Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4886633 | Method for manufacturing stones in a press | Cornelis Rook | 1989-12-12 |
| 4856976 | Device for manufacturing stones | Cornelis Rook | 1989-08-15 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4886633 | Method for manufacturing stones in a press | Cornelis Rook | 1989-12-12 |
| 4856976 | Device for manufacturing stones | Cornelis Rook | 1989-08-15 |