love'em, love emeralds although I haven't clue about the feather-in-your-cap mark, I do know that green emeralds are rare gems. The color of the emeralds are the most important consideration. Worldwide, Coumbia produces the most emeralds , they come from the Muzo, Coscuez and Chivor mines.
Unlike diamond where the loupe standard i.e. 10X magnification is used emerald is graded by eye. If emerald has no visible inclusions to the eye (assuming you have normal vision) it is considered flawless. Because emeralds are rare and valuable synthetic emeralds are produced. Good luck with that mark.
