We offer alchemie gases is the first company to introduce high quality & accurate ã¢ï¿½ï¿½natural gas mixtureã¢ï¿½ï¿½ in the indian market. We have now added bio gas and coal bed methane (cbm) to our product list. each mixture is prepared gravimetrically in accordance with iso 6142 and analyzed in accordance with national /international standard iso 6143, alongwith following standards i.e. iso 6974 or astm d 1945, iso 6976 for calculation of calorific value or astm d 3588-98 or gpa 2172 for calculating heat value