Tian Zhu Huang

Tian Zhu Huang, known in English as tabasheer or bamboo silica, is a siliceous concretion that forms naturally inside the hollow internodes of certain bamboos, principally Bambusa textilis McClure and related species in the grass family Poaceae. As the bamboo culm grows, silica taken up from the soil precipitates from the internodal water into a translucent to opaque, milky white or pale bluish-white amorphous mass of hydrated silicon dioxide (opal-like SiO2·nH2O) with traces of plant organic matter. The concretion is liberated by splitting mature culms in winter, harvesting the lumps, and drying them; the substance is soft, light, sticks to the tongue when touched, and dissolves slowly in water. In traditional Chinese medicine the powdered concretion is sweet and cold, clearing heat from the heart and liver channels to relieve childhood febrile convulsions and high fever with delirium, and transforming hot phlegm to ease cough, wheezing, and stroke-related loss of speech.