DAMMAR, a resin derived from various plants, principally Agathis danmiara and A. australis, both members of the pine family, or the trees themselves. These are natives of Molucca and the East India Islands, also of the Philippines and New Zealand. Danunar is exuded from the main stems and also from the roots of the plants. Fossil dammar is called kauri (q.v.). In some regions, notably in the mountains of Sumatra, the resin bursts forth in profusion from spontaneous fissures. In other regions artificial incisions are made in the trees, with a yield of resin correspondingly greater. Dammar comes into the market in large masses, or small pieces. It is yellowish, transparent when in small pieces, smooth and brittle, breaking with a clean, glassy fracture and it is readily reduced to powder. It is inter mediate in hardness between colophonium and copal. Chemically it contains traces of ethereal
oil, dammarolic acid and two resins. It is widely used in the manufacture of varnishes.
The same name is applied in commerce to the resin of other and unrelated trees. Thus the dammar of shipyards is obtained from a species of Canarium, an amyridaceous tree, while black dammar is a kind of pitch derived from the same genus. Shores robusta, a tree, yields pitch and resin used in Indian dockyards, and some times also called dammar. Dammar is also occasionally confused with kinds of copal; thus, the resin of Valerie indica (Dipteracece) is sometimes known as dammar or piny dam mar, of which the piny varnish of India is com pounded. One of the Australian species, A. robusta, has been grown in some parts of Cali fornia with fair success.