Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5559061 | Gem comprised of a glass based on silicon oxide and calcium oxide | Norbert Bilek, Wolfgang Porcham, Gerold Sprachmann | 1996-09-24 |
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5559061 | Gem comprised of a glass based on silicon oxide and calcium oxide | Norbert Bilek, Wolfgang Porcham, Gerold Sprachmann | 1996-09-24 |