GEOLOGY

The emerald-bearing rocks overlie a dark mica schist and are covered by a lighter, green chlorite-tremolite schist. The chlorite-tremolite schist grades into talc schist beneath.

The emerald-bearing formation consist of dolomitic talc schist.

Lenses of ultamafic and talc-carbonate rocks are intercalated in the shear zone.

The thickness of talc-schist has been affected by rock movements.

A break is noted between the talc schist and mica schist:  it consist primarily of a dark mica within layer of quartz and dark grey limestone.

Underneath, there are a sedimentary and calcareous layers: arenaceous, argillaceous and carbonatic rock. Underlying that is an older ultramafic dike of amphibolites and finally a younger intrusion of granodiorite called the Boner schistose group.

In the region of Mingora the schists are almost vertical.

The talc schist which hosts the emeralds is intruded by a series of serpentinized ultramafic dikes and, because of thrusting, it repeated four times. In the upper part there is a lack of emerald because there it lacks the quartz vein interlinked with calcite that characterizes the lower beds. This combination, quartz and calcite, becomes dominant in the lower part.