A wide variety of pegmatites occur in this district. The largest pegmatite Malakialina A-4 was abandoned in 1963, having prduced some 2000 metric tons of beryl
and 32 metric tons of columbite. Enormous prisms of beryl
, up to 1 meter in diameter and many meters in length, were recovered in the largest dikes. The largest crystal reported by Besairie was found in 1966, was 8 meters long, and weighed 32 metric tons.
Ref: Madagascar, extraLapis English No.1, 2001, p. 62