In ovoid, more or less spheroidal tears, or in broken, angular fragments from 2 to 30 mm. in diameter, varying from white or yellowish white to light amber-colored; translucent; very brittle; fractured surface glass-like, sometimes iridescent; nearly inodorous; taste insipid, mucilaginous.

Insoluble in alcohol; slowly and almost completely soluble in twice its weight of water, forming a mucilaginous liquid, which has a slight characteristic odor and is acid to litmus. When either 0.1 mil of basic lead acetate T.S., or 0.1 mil of a concentrated solution of sodium borate, or 0.1 mil of ferric chloride T.S. is added to 10 mils of a 10 per cent. aqueous solution of Acacia, a gelatinous precipitate is produced. The precipitate produced with ferric chloride T.S. is neither black nor brownish-black (tannin).

The powder is whitish, with few or no starch grains or fragments of vegetable tissues.

Not more than 1 per cent. of powdered Acacia is insoluble in water (plant tissues, sand, or dirt).

Acacia yields not more than 4 per cent. of ash, and the powder contains not more than 15 per cent. of moisture.

Preparations--Mucilago Acaciæ. Syrupus Acaciæ.