.	Dwarves' Earth Treasures Online Museum: Iron City (Empire) Datolites Iron City (Empire) Mine, Copper Harbor, Keweenaw CO., Michigan	.

.    I know very little about Iron City (Empire) Mine between Deleware and Copper Harbor, MI and that mien is known for producing the orange datolites and rarely very coarse nodules. The datolites from that mine seemed to have came and gone very quickly as if that site was short-lived and I don't know why some people refer that mine as "Empire" while others refer it as "Iron City".