- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
"Idiomorphic, pale blue corundum crystals (S.G. = 4.02, n o = 1.770 + or - 0.002) up to one inch long occur as porphyroblasts in a fine-grained biotite-sillimanite gneiss cut by pegmatite veins at Gangoda, 5 1/2 miles south of Polgahawela. The field relations and petrography of the corundum-bearing rocks are described briefly. The corundum is thought to have crystallized by metamorphic differentiation in alumina-rich silica-poor bands in a semipelitic gneiss."