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Use and treatment of the black schists carbonaceous, of the mountain of lions, near oran, and all other of the same nature and composition of the same for the extraction and the manufacture of a 'black mineral' and 'ochres slicks ' adapted to the paint and to the coloration of industrial products
Use and treatment of the black schists carbonaceous, of the mountain of lions, near oran, and all other of the same nature and composition of the same for the extraction and the manufacture of a 'black mineral' and 'ochres slicks ' adapted to the paint and to the coloration of industrial products