Granted Patent
Utility
US 5,250,272 · App. 07/899,588
Process for leaching precious metals with hydrogen-peroxide and a cyanide leaching solution
Inventors:
Helmut Knorre, Juergen Loroesch, Steven Gos, Mathias Stoll, Annette Ziegler
Patented Case
View Patent ↗
Granted: Oct 5, 1993
Filed: Jun 18, 1992
Inventors
Helmut Knorre
Juergen Loroesch
Steven Gos
Mathias Stoll
Annette Ziegler
Assignee (at issue)
Degussa AG
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.