Granted Patent
Utility
US 4,929,274 · App. 07/362,896
Recovery of metal values from ores
Inventor:
Lionel B. Luttinger
Patented Case
View Patent ↗
Granted: May 29, 1990
Filed: Jun 7, 1989
Inventor
Lionel B. Luttinger
Assignee (at issue)
Drew Chemical 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.