Patent ID: 7420657

Claim:
A computer-implemented method, comprising: generating a representation corresponding to an illuminated image of a gemstone viewed from an observation location, wherein said representation differentiates between light rays incident on said gemstone from a first range of incident angles and light rays incident on said gemstone from a second range of incident angles; evaluating said gemstone based on light rays said gemstone directs to said observation location which were incident on said gemstone from an angle within said first range of incident angles; and providing results from said evaluating to a user; wherein said gemstone is evaluated based on light rays of a first wavelength said gemstone directs to said observation location which were incident on said gemstone from an angle within said first range of incident angles and on light rays of a second wavelength the gemstone directs to said observation location which were incident on said gemstone from an angle within said first range of incident angles.