Glossary
Facet
A polished surface on a diamond.
Fire
Fire is the amount of colored light reflected from within a diamond. White light entering a stone is
separated into the many colors of the rainbow just like a prism. Good fire can only be achieved with
very good to excellent proportions. Also called "refraction" or most often "dispersion" in the trade.
Fluorescence
A glow which emanates from certain diamonds when exposed to ultraviolet light. Strong fluorescence
should be avoided, but faint fluorescence usually does not affect the appearance of a diamond. In fact,
faint or moderate blue flourescence is preferred by some customers because it can make a less expensive
yellowish color appear more white or colorless in daylight.
Fractures
Fractures are caused mainly by mechanical stresses like pressure or impact and may run in all directions
within the diamond.