zinc ore to processing for zinc sulphate

US1496004A US349574A US34957420A US1496004A US 1496004 A US1496004 A US 1496004A US 349574 A US349574 A US 349574A US 34957420 A US34957420 A US 34957420A US 1496004 A US1496004 A US 1496004A Authority US United States Prior art keywords zinc solution copper iron leaching Prior art date 19200105 Legal status The legal status is an assumption and is not a legal