Granted Patent
Utility
US 5,939,034 · App. 08/878,263
Process for the recovery of precious metal values from aqueous ammoniacal thiosulfate leach solutions
Inventors:
Michael J. Virnig, J. Michael Sierakoski
Patented Case
View Patent ↗
Granted: Aug 17, 1999
Filed: Jun 17, 1997
Inventors
Michael J. Virnig
J. Michael Sierakoski
Assignee (at issue)
Henkel Limited
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.