DIAMOND GEM-CUTTING STRUCTURE PROVIDING MULTIPLICITY OF VISUALLY PERCEIVED DIFFRACTED BEAMS FOR DECORATIVE USAGE AND METHOD FOR EVALUATING THE SAME Russian patent published in 2007 - IPC A44C17/00 

FIELD: decorative diamond gem-cutting structure and method for evaluating of diamond.

SUBSTANCE: gem-cutting structure is made in the form of round diamond gem-cut comprising rundist, crown above rundist and pavilion under rundist. Height of rundist is 0.026-0.3 the radius of rundist, angle of pavilion of rundist main facet is ranging between 37.5 deg and 41 deg, and angle of main facet of crown is within the range conforming to the following ratios: c>2.8667xp+134.233 and p<1/4x{sin^-1(1/n)+sin^-1 (1/n˙sinc))x180/π +180-2c}, where n is diamond diffraction ratio; π is circle constant; p is angle of pavilion, deg; c is angle of crown, deg. Decorative diamond cutting design presents multiplicity of visually perceptible diffracted beams, when observer contemplates diamond on the side of pavilion facet at sight angle less than 20 deg relative to vertical line extending through center of facet of platform.

EFFECT: increased number of perceived diffracted beams to impart additional aesthetic attractiveness to diamond.

13 cl, 43 dwg