Patents Assigned to Gem Instruments Corporation
  • Patent number: 5378032
    Abstract: An improved stoneholder for supporting diamonds and other gemstones comprising a pair of clasping members and a pair of respective clasp mounts. Each clasping member comprises a pair of stone support members which are joined at a distal end, separated by an aperture, and mounted to one of the respective clasp mounts at a proximal end.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: January 3, 1995
    Assignee: GIA Gem Instruments Corporation
    Inventors: Richard C. Agnew, Robert Van Den Heuvel
  • Patent number: 5242203
    Abstract: An improved stoneholder for supporting diamonds and other gemstones comprising a pair of clasping members and a pair of respective clasp mounts. Each clasping member comprises a pair of stone support members which are joined at a distal end, separated by an aperture, and mounted to one of the respective clasp mounts at a proximal end.
    Type: Grant
    Filed: January 24, 1992
    Date of Patent: September 7, 1993
    Assignee: GIA GEM Instruments Corporation
    Inventors: Richard Agnew, Robert Van Den Heuvel
  • Patent number: 4266871
    Abstract: An apparatus visually duplicates the hue, tone, intensity and shape of a selected gemstone by combining predetermined intensities of red, green and blue light sources within a color mixing box. A single variable intensity light source and a monochromatic filter provide each of the three colors. Colored light from each light source is passed through a portion of a multi-segment diffusion lens prior to entering the color mixing box. The three separate colors are combined within the color mixing box and reflected from an image wheel which includes various geometric patterns. Light propagated from the color mixing box passes through a silhouette wheel to a crystal wheel which provides an appropriate gemstone shape. The light then passes through an image magnifier which controls the apparent size of the gemstone. Controls are provided to modify the shape, color and intensity of the duplicated gem displayed by the apparatus.
    Type: Grant
    Filed: July 28, 1978
    Date of Patent: May 12, 1981
    Assignee: Gem Instruments Corporation
    Inventor: Thomas F. Ritzi