Granted Patent
Utility
US 4,640,823 · App. 06/839,093
Alkaline leaching of vanadium bearing residues
Inventor:
John Goddard
Patented Case
View Patent ↗
Granted: Feb 3, 1987
Filed: Mar 13, 1986
Inventor
John Goddard
Assignee (at issue)
U.S. Vanadium Corporation
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.