Abstract
Theophrastite (Ni(OH)2) was found from a Fujiwara metaperidotite, the Sanbagawa belt, Ehime Prefecture. Antigorate, olivine, magnetite, chromite and Ti-clinohumite are the main minerals, with small amounts of sulfides (e.g., heazlewoodite), awaruite and arsenides. Theophrastite is closely associated with heazlewoodite, and is interpreted as its hydration decomposition at a low-T condition.