2690903

Information

• Patent Grant
• 2690903

• References
• Source

• Patent Number

  2,690,903

• Date Filed

  Not available

• Date Issued

  Tuesday, October 5, 1954
  70 years ago

• CPC

  • E21C27/46 - by percussed planing means

• US Classifications

  • 299 - Mining or in situ disintegration of hard material