deposit in the southern part of the state of Bahia near the town of Brumado. The emerald
mineralization is in dolomite marbles underlain by a gneiss-schist sequence. The dolomites are strongly altered, with the development of thick zones of talc, containing phlogopite, kyanite, and tourmaline. Veins and lenticular calcite occur in these zones. Emerald
and sporadic topaz crystallized in the central cavity of the veins. The emerald
has a distinct prismatic habit, but raw material is mainly used for cabochons because its quality is low.
Ref: E.Ya. Kievlenko (2003) Geology of gems, p. 95