MINERALIZATION
The emeralds occur within small veins that fill fractures in the host
rock.
The host rocks are metamorphosed limestones, calcareous
slates, phyllites, and micaceous schist of Silurian-Devonian age. The
veins consist mainly of quarzt-albite, apparently related to a local
igneous intrusive rock described as a quartz-feldspar porphyry. The
emeralds are believed to be of hydrothermal origin and resulted from a
chemical
reaction between solutions travelling along the fractures and the
enclosing
host rocks.