In addition to copper the “poor rock” from the mines in the Keweenaw contains a number of other minerals.

 

Below is a list of some of the more common ones.

 

White - Calcite or Quartz

Blue – Chrysocolla

Light Green - Prehnite

Grass Green - Epidote

Dark Green – Chlorite, Chlorastrolite

Pink – Prehnite (with copper)

Orange – Laumontite

Red – Microcline(feldspar)

Copper – Copper :-)

Silver – Silver ;-)