Schäferite is a rare vanadate mineral with chemical formula Ca2NaMg23. Schäferite is isometric , which means that it has three axes of equal length and 90° angles between the axes. Schäferite is isotropic, meaning that the velocity of light is the same no matter which direction the light passes through.
It was named after Helmut Schäfer (born 1931) who discovered it in a quarry on the Bellerberg Volcano It is found only in the Eifel Mountains, Laacher See in a leucite. It is the magnesium analogue of palenzonaite and is a member of the garnet structural group