Copper Replacement Agate-
Wolverine #2 Copper Mine, Houghton Co. Michigan.
2.5 cm across.
These are copper (infused) replacement agates, the rarest agates to date. They were formed in the Kearsarge lode of basalt from the Kearsarge/Calumet Michigan area. They are only found in this lode.
Molten copper rose and mixed with silica material as the agates were being formed in small vesicles creating glistening bands of pure copper alternating with agate material.