Chantalite, CaAl₂SiO₄(OH)₄, occurs with vuagnatite, prehnite, hydrogrossular, chlorite and calcite in rodingitic dykes from an ophiolitic zone in the Taurus Mountains, southwest Turkey. The name is for Mrs. Chantal Sarp. Both name and mineral have been approved by the Commission on new Minerals and Mineral Names of the International Mineralogical Association. Electron microprobe analysis has shown the uniform distribution of the major elements and the absence of other components. X-ray powder diffraction data are from a Gandolfi camera. The crystal system is tetragonal, and the cell parameters are: a = 4.945 (3), c = 23.27 (2) Å. The probable space group is I4₁/a. The major X-ray diffraction lines occur at 5.810, 4.828, 4.171, 3.349, 2.598, 2.235, 2.202, 1.749, 1.529, 1.453 and 1.301 Å. Crystals are always anhedral, varying in size between 0.1 and 0.3 mm. The measured density is 2.8-2.9 g/cm³, the calculated densitiy being 2.97 g/cm³. The difference is due to difficulties in getting material free of inclusions. The refractive indices are: ω = 1.653, ε = 1.642, optically negative. The crystallization of chantalite is related to metasomatic processes of rodingitization.