·noun A rare metallic element, found in certain zinc ores. It is white, hard, and malleable, resembling aluminium, and remarcable for its low melting point (86/ F., 30/C). Symbol Ga. Atomic weight 69.9.
II. Gallium ·add. ·noun A rare metallic element, found combined in certain zinc ores. It is white, hard, and malleable, resembling aluminium, and remarkable for its low melting point (86° F., 30° C.). Symbol, Ga; at. wt., 69.9. Gallium is chiefly trivalent, resembling aluminium and indium. It was predicted with most of its properties, under the name eka-aluminium, by Mendelyeev on the basis of the periodic law. This prediction was verified in its discovery (in 1875) by its characteristic spectrum (two violet lines).