E 
J.D. Whitney on Minerals of the Lake Superior region. 9 
and Northwestern mines; and, especially, at the last-named 
place, where work is, for the present, suspended. Both these 
mines are, in fact, on the same vein, the Copper Falls mine being 
to the north, and the Northwestern to the south of the great 
belt of crystalline, unproductive trap, which runs through the 
middle of Keweenaw Point. In this vein, analcime occurs in 
large and almost transparent crystals forming geodes in the 
greenish magnesian silicate which is the principal gangue of the 
vein. These crystals are all trapezohedrons, and sometimes 
occur an inch in diameter; they occasionally have a thin in- 
crustation of chrysocolla. The analcime, at this locality, is 
almost always associated with the peculiar form of orthoclas 
So common in the copper region, and which will be noticed 
farther on. 
At the Old Copper Falls vein analcime has been found in ra- 
diated-fibrous as well as granular-massive forms, and of a bright 
red color. 
Apophyllite—The foliated variety, or ichthyophthalmite, was 
found in great abundance in 18538 in the rubbish thrown out at 
the workings on the Prince vein, on the north shore. A variety 
in small, brilliant, deep-red crystalline scales or spangles, dis- 
seminated through calcite, forms curious and elegant specimens. — 
The most usual occurrence of apophyllite at this locality is in 
large contorted plates, somewhat resembling the variety of cal- 
cite known as argentine. Crystalline specimens are occasionally 
met with at the Cliff mine, but none have been noticed in the 
Ontonagon district. 
Barytes—There are numerous veins of sulphate of baryta on 
the north shore of the Lake, and especially along that portion 
lying to the northwest of Isle Royale, as also on that island, and 
the smaller ones which lie near the main land to the westwar 
of Thunder Bay. These veins vary in width from a few inches 
to several feet, and are usually made up of quite compact barytes 
without crystallization, and destitute of accompanying metallif- 
erous ores. oe 
The famous “ Prince vein,” on Spar Island, is one of the most 
conspicuous and interesting objects, at least in the eye of the 
: ects, oa e. 
ctnlcaias in this region. As it makes its appearance on the 
ide of the island, on the precipitous face of the trap cliffs, 
lake. At the southern edge of Spar Island it is fourteen: feet 
SECOND SERIES, Vor. XXVIII, No. 82.—JULY, 1859. 
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