Gamboge

Gamboge, a gum-resin obtained from the bark of Garcinia Hanburii, G. Morella. and allied species of that genus of the order Guttiferae or Clusiaoeae, trees, with apposite, glossy, leathery leaves, natives of Siam, Cambodia. Cochin China, Ceylon, and Southern India. Gamboge occurs in "pipes" or "rolls" and in lumps. It is of a dirty orange externally, hard, brittle, with a conchoidal fracture, and odourless. It contains 20 to 25 per cent. of gum, with 70 to 75 per cent. of the resin gamhpgic acid. Britain imports from 10 to 30 tons annually, mainly from Bangkok and Saigon. It is used as a pigment, for colouring varnishes, and as a purgative.