Cut and Value (Assignment 4) Flashcards
PROPORTIONS
The angles and relative measurements of a polished gem, and the relationships between them.
FINISH
The quality of the polish and precision of the cut of a fashioned gemstone.
MAKE
The qualities of a faceted diamond’s proportions and finish.
REFRACTION
The change in speed and possible change in direction of light as it travels from one transparent material to another.
REFRACTIVE INDEX
A measure of the change in the speed and angle of light as it passes from one material to another.
DISPERSION
The separation of white light into spectral colors.
GIRDLE OUTLINE
Face-up shape of a polished gem.
SHOULDERS
One of the two sides adjacent to the rounded end of a pear or oval shape.
AVERAGE GIRDLE DIAMETER
The result achieved by adding the smallest and largest girdle measurements of a round brilliant and dividing by two.
TABLE PERCENTAGE (SIZE)
Table size expressed as a percentage of a round brilliant’s average girdle diameter.
PAVILION DEPTH PERCENTAGE
The distance from the bottom of the girdle plane to the culet, expressed as a percentage of the average girdle diameter.
PAVILION BULGE
Larger-than-usual pavilion angles on the middle tier of facets, designed to add weight to a step-cut stone.
PAVILION ANGLE
The angle formed by the pavilion main facets and the girdle plane.
TOTAL DEPTH PERCENTAGE
Table-to-culet depth, expressed as a percentage of average girdle diameter.
LENGTH-TO-WIDTH RATIO
Comparison of the length to the width of a fancy-shaped diamond.
