Baoruco Mountain Range (Bahoruco Mountain Range, Sierra de Baoruco) is situated in the Baoruco Province in the far southwestern corner of the Dominican Republic. It is noted for the blue colored concretions called larimar which formed in the volcanic vesicles.
Part of the area has been set aside as the Sierra de Bahoruco National Park (Parque Nacional Sierra de Bahoruco).
Larimar is the name in the Dominican Republic for the mineral assemblage of acidic silicate hydrates of calcium and sodium. Larimar is a specific type of pectolite (occasionally as ratholite), a pyroxenoid mineral.