Major allbite deposits in metamorphic Menderes Massif (western Turkey). Albite deposits of western Turkey occur within gneiss in the basal part of the Menderes Metamorphic Massif. The most important deposits are located along the Karadere mineralization zone, within an anticlinorium of 15-km length with a direction of N10-30E. Detailed study of the four deposits forming the northern part of this zone has allowed us to discover large reserves of 100.65 million tons, of which 78% is composed of high-grade ore with a content of 10.27% Na2O. The remainder is formed by low-grade ore with 8.37% Na2O and 1.11% K2O and mixed ore with 4.61 % Na2O and 4.05% K2O, with reserves of 14.4 and 8.2 million tons, respectively.