nambulite

{{Infobox mineral | name = Nambulite | category = Inosilicate | boxwidth = | image = Nambulite-136231.jpg | imagesize = | caption = Gem quality nambulite from the Kombat Mine near Otavi, northern Namibia (size:  cm) | formula = | IMAsymbol = Nbl | molweight = | strunz = 9.DK.05 | system = Triclinic | class = Pinacoidal () (same H-M symbol) | symmetry = P | unit cell = , ; , ; | color = Reddish orange brown | habit = Prismatic | twinning = infrequent | cleavage = {001} perfect, {100} distinct, {010} distinct | fracture = | tenacity = Brittle | mohs = 6.5 | luster = Vitreous – adamantine | refractive = | opticalprop = Biaxial (+) | 2V = (calculated) 44°, (measured) 30° | dispersion = r > v weak | birefringence = δ = 0.023 | pleochroism = Weak | streak = Pale yellow | gravity = 3.51 | density = | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Transparent to translucent | other = the Li analogue of natronambulite | references = }}

Nambulite is a lithium bearing manganese silicate mineral with the chemical formula . It is named after the mineralogist Matsuo Nambu (born 1917) of Tohoko University, Japan, who studies manganese minerals. It was first discovered in the Funakozawa Mine of northeastern Japan in a metasedimentary manganese ore.