Patent Number: 050849093
Section: claims

1. A method of processing a gemstone to enhance its color comprising: heating the gemstone to a temperature of between about 150 and 1,100 degrees Centigrade for a period of between about fifteen minutes and fifty hours; and then  irradiating the gemstone with gamma rays to give a total exposure of between about 200 and 10,000 megarads.  irradiating the topaz stone with neutrons;  heating the topaz stone to a temperature of between about 300 and 600 degrees Centigrade; and  irradiating the gemstone with about 3 to 25 MEV gamma rays to give a total exposure of between about 200 and 10,000 megarads. 2. A method according to claim 1 wherein the gemstone is topaz previously irradiated with neutrons, and the topaz is heated to a temperature of between about 300 and 600 degrees centigrade prior to irradiation with about 3 to 25 MEV gamma rays. 3. A method according to claim 1 and further comprising the step of heating the gemstone after gamma ray irradiation thereof to a temperature between about 160 and 1,100 degrees centigrade for a period of between about fifteen minutes and fifty hours. 4. A method according to claim 1 wherein the gamma rays have a flux between about 0.5 MEV and 30 MEV. 5. A method according to claim 1 and further comprising the step of irradiating the gemstone with neutrons prior to gamma ray irradiation. 6. A method according t claim 5 and further comprising the step of irradiating the gemstone with electrons after the neutron irradiation and prior to the gamma ray irradiation. 7. A method according to claim 5 wherein the neutron irradiation is between about 1,000 and 10,000 megarads. 8. A method according to claim 6 wherein the electrons are provided in the form of a beam having a flux of between about 8 and 17 MEV. 9. A method according to claim 1 wherein the gemstone is selected from the group consisting of topaz, beryl, tourmaline, quartz and diamond. 10. A method of processing a topaz stone to enhance its color comprising: 11. A method according to claim 10 wherein the heating takes place for a period of between about fifteen minutes and fifty hours. 12. A method according to claim 10 and further comprising the step of heating the topaz after gamma ray irradiation thereof to a temperature between about 160 and 1,100 degrees Centigrade for a period of between about fifteen minutes and fifty hours. 13. A method according to claim 10 and further comprising the step of irradiating the topaz stone with electrons after the neutron irradiation and prior to the gamma ray irradiation. 14. A method according to claim 13 wherein the electrons are provided in the form of a beam having a flux of between about 8 and 17 MEV. 15. A method according to claim 10 wherein the neutron irradiation is between about 1,000 and 10,000 megarads.