Geologically speaking, Colombian  emeralds  are  said  to be the purest emeralds in the world because Colombian emerald deposits are the only ones

 on  earth  found  in  sedimentary  host  rock  rather  than  in  Igneous  rock.  The tectonic movements that created the Andes Mountains force the raw 

materials of emeralds — beryllium, chromium, and vanadium—found in the ground into liquid and gaseous states. These materials, in such states, find 

their  way  into  cracks  in  the  already  sedimentary  medium  surrounding them and then eventually cool and crystallize. A saline solution found in the 

sedimentary  rock  eventually  washes  out  impurities  such  as  iron  that  cloud  other  beryls  from  forming  onto  the crystallizing stone. This intricate 

process  produces the emeralds found in the mines of Colombia.

An  emerald  is actually a beryllium stone that owes its special color to beryllium, chromium, and vanadium, all of which are

 chemical elements that are very scarce, and the reason for the color of an emerald. Colombian emeralds are much sought 

after, and not just because of their superb quality and color. A gem's value depends upon its size, purity, color and brilliance. 

Even when they are mined in the same area, each individual emerald has its own unique look that sets it apart from the rest. 

Dark green is considered to be the most beautiful, scarce, and valuable color for emeralds. But,…often beautiful emeralds that

are lighter in color with good clarity and life make the most exquisite jewelry!