Granted Patent
Utility
US 5,573,307 · App. 08/468,795
Method and apparatus for blasting hard rock
Inventors:
G. Mark Wilkinson, Steven G. E. Pronko
Patented Case
View Patent ↗
Granted: Nov 12, 1996
Filed: Jun 6, 1995
Inventors
G. Mark Wilkinson
Steven G. E. Pronko
Assignee (at issue)
Maxwell Laboratories, Inc.
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.