The dried rhizome: Flattened cylindrically, often curved and branched; 3 - 20 cm long and 0.3 - 1 cm in cross-section;
brown or gray-brown, rough surface with nodial rings, is the internodial length 0.2 - 0.8 cm.
Hard consistency; fibrous, whitish or slightly reddish-colored fracture with clearly visible endodermis ring,
Numerous point - shaped vascular bundles and brown oil passages.
Smell: aromatic;
Taste: bitter, slightly sharp