Process for irradiating gemstones
US5637878A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 1995 |
| Grant date | Jun 10, 1997 |
| Priority date | — |
| Expiry date | Feb 3, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG21K5/10
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A method the electron-beam irradiation of gemstones for uniform color enhancement requiring an electron-beam source having a capacity of 500 kW generating energy of between 3 MeV to 50 MeV. The method requires the gemstones to be moved in and out of the electron-beam path with the electron-beam source also being oscillated but in a direction ninety degrees opposed to the gemstones. Cooling means for the gemstones are also required to prevent heat stress cracking. Gemstones such as beryl, diamonds, quartz, sapphires, tourmaline, dark pearls and other minerals are suitable. More particularly the method relates to the treatment of topaz.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.