Granted Patent
Utility
US 6,755,891 · App. 10/122,346
Process for the treatment or removal of impurities in a hydrometallurgical extraction process
Inventor:
David L. Jones
Patented Case
View Patent ↗
Granted: Jun 29, 2004
Filed: Apr 16, 2002
Inventor
David L. Jones
Assignee (at issue)
Cominco Engineering Services Ltd.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.