10 J.D. Whitney on Minerals of the Lake Superior region. 
and seven inches wide. Here the vein is made up of a of 
calcite, crystalline ceils and barytes, as represented by the 
nexed cross-section 
bh ads — 6’ 1” 
rap; ‘ 5, coarsely eo calcite; ¢, barytes; d, calcite with copper 
pyri: ts quartz and calcit 
At the point where this section was taken the ore is confined 
' toa band of calcite in the centre of the vein and about six inches 
in width. The metalliferous portion of the lode consists here of 
chalcopyrite and erubescite,—in small quantity, however, - 
compared with the amount of barren veinstone connected with 
these ores. 
On the main land, about two miles distant, the vein reappears 
a little way back from the shore, where it is much split up; 
iit boone Rat m ates rods farther to the northwest it con- 
least, would be gat red, the vous "bein highly crystalline 
in its texture. feat saotalliferoas contents, however, seem to 
chiefly limited to blende. At the point in the level where a 
winze has been sunk to the depth of 90 feet, and near the collar 
of the winze, a considerable quantity of native silyer was ob- 
tained in fine laminze between the joints of the blende. A large 
Te no other vein in this ee eaheete were any interesting 
eee nae minerals baeaegd ia although the exposures on the 
e shore are usually g 
Chalybite—This Tia has been observed by Dr. G. H. 
Blaker 1 in the taleose slates near Marquette; it forms narrow 
i igh the slates. The quantity is not suflicient to make it 
economical | importance. 
edna mineral occurs, associated xP chalcopyrite, in the 
quartz veins at Echo Take, near Saut St. Marie. The geological 
em of ‘these veins is the same as that of the Marne 
s and bunches in the veins of milky quartz which ramify . 
