Method of detection of natural diamonds that have been processed at high pressure and high temperatures
US6377340B1 · kind B1 · utility
14Cited by
12References
69Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 29, 1999 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | Oct 29, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/87
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for detecting whether a natural diamond has been processed at high pressure and high temperature (HPHT) conditions comprises steps of disposing the diamond in a cyrostat that is provided at temperatures equal to or less than liquid nitrogen; illuminating the diamond with a laser beam; recording an optical spectrum of the diamond with a photoluminescence spectrometer; and examining the optical spectrum of the diamond to detect an absence of selected photoluminescent spectral lines. The invention also sets forth a method for predicting whether a natural diamond has been treated under HPHT conditions
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.