PT GMR | Indonesian Marble Quarry and Industry. PT. Gunung Marmer Raya (GMR) has been in the marble business since 1998. The company own a quarry and processing facilities in the Pangkep area, about 60 kilometers from the city of Makassar, which is also known as Ujung Pandang, in the province of South Sulawesi (also known as Celebes), Indonesia.