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A List of Minerals and Organic Remains. 67 
and some small but brilliant garnets. I noticed a vein of 
massive garnet, one foot thick, in an isle three miles east 
rom Bourassa’s House. I found a loose mass, two hun- 
dred and fifty pounds weight, eleven miles east of the 
French River, of sienite, composed of black hornblende 
and gray feldspar, having a very strong purple iridescence. 
The hornblende must, therefore, occasionally be abundant 
in this rock. 
The Labrador feldspar is of greenish bluish, and bya- 
line gray, in facets, usually about half an inch in diameter ; 
but often much larger. ‘Fhe iridescence is purple, green, 
and rarely flame colored, and is only observed in a few soli- 
tary spots until dipped in water, or polished, when it over- 
spreads nearly the whole mass. 
Judging from the extensive range of country over which 
bowlders of Labrador feldspar are scattered, the fixed rocks 
consisting of this mineral with which I met in Lake Huron, 
are only the southern portion of a large deposit situated in 
the unexplored forests included between Lakes Simcoe, 
Huron, Nipissing and the Ottawa or Grand River. From 
the French River, eastwards, the Labrador feldspar over- 
spreads the northern parts of Lake Huron in vast quanti- 
ties, seldom however very iridescent. “ars sandy Hills* 
h d 
of the east shore of that lake,* an ke Simcoe are 
loaded with it ;—and it is traced, rapidly diminishing in 
quantity, across Lake Simcoe to Ontario, lying upo 
great beds of clay and sand which occupy this interval. — 
Even as far down the north shore of Lake Ontario as Kings- 
ton, solitary masses may be observed. 
The small bowlders of blue Labrador feldspar found by 
my friend Dr, Lyons in the Island of St. Helen, opposite 
to Montreal, I scarcely believe to belong to this formation 
as it forms part of a micaceous aggregate, is whiter, and can 
be referred to a nearer origin, Lake Champlain. 
Mica.--Ottawa River at the portage of the Grand Ca- 
lumet, 200 miles from Montreal, in what I suppose to be 
Dolomite, subordinate to primitive white marble. It is in 
Unequiangular six sided tables. ‘ 
* Containing horizontal layers of alasmadonta, cyclades, planorbis, &c, 
and frequently several miles inland from the present shore of the La 
ee 
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