Home / Standards / GB/T 4291-2017 GB/T 4291-2017 Active Synthetic cryolite 冰晶石 Standard Type GBT ICS 71.100.10 CCS D59 Status 现行 Issue Date 2017-07-12 Implementation 2018-02-01 Responsible Dept 中国有色金属工业协会 Drafting Unit N/A