Title: Pyramid cut used on Calumet conglomerate lode drifting
Photographer: Unknown
Subject Headings: Metal Trade - Copper Industry and Trade - Copper Mines and Mining, Engineering - Surveying,
Condition: Good
Description: Pyramid cut used on Calumet conglomerate lode drifting [Sketch map showing number and direction of shot holes drilled within a typical drift of the underground workings on the Calumet conglomerate ore body. After drilling, these holes would be filled with explosives and fuses which would ignite the charges in the numeric order indicated.]
Source of Description: [cataloger]
Institution: Michigan Technological University Archives and Copper Country Historical Collections
Donor:
Date of Photo: October 1931
Medium: still image
Color: color
Size: 13.0 cm x 7.0 cm
Polarity: Positive
Image No: Book TN443M5V5-008 Figure 6
Collection Name: Book Collection
Terms of Use: Rights to reproduce and distribute this image may be restricted. Contact the Michigan Technological University Archives and Copper Country Historical Collections for further information.
Please login if you would like to comment on this image.