MAGNETITE IRON DEPOSITS OF SOUTHEASTERN NEW YORK III 
in depth is a reasonable assumption, although this has not yet been 
tested by actual exploration; the old workings, with the exception of 
the Sunk mine, being shallow and little more than prospect pits and 
trenches. 
THE CANADA MINES GROUP 
The Canada mines group consists of the Canada, Sunk (or 
Stewart), Sackett, Pratt, and Denny mines, lying in the order 
named, from north to south along Canopus creek (see fig. 11). 
The Canada mine. The Canada workings are a series of shal- 
low cuts and trenches along the strike of the ore, north 40° east, 
involving a total distance of nearly 2 miles. The dip of the ore 
body is steep to the southeast, but in places, more particularly toward 
the south end of the workings, it varies to 60° as a minimum. 
Where the ore is exposed it shows thicknesses varying from 3 to 
15 feet, the middle portion being solid ore, which grades toward the 
walls into stringers and bands mixed with rock; sharp contacts do 
not exist. 
The walls are gneissoid in structure, and petrographically prove to 
be in part quartz-bearing syenites, judged to be related to the 
Pochuck, since farther south along the ore-belt this also appears in 
more typical facies, and because here and there pegmatite is 
developed, always closely associated with the ore and related to 
the rock. 
A specimen from the footwall consists of acid plagioclase with 
strongly crenulated margins, in places granulated; a very small 
quantity of interstitial and granular quartz, a little uralitized 
pyroxene, and epidote and tourmaline in interstitial distribution and 
related to the closing stages of crystallization. The granulation, bent 
twinning and strain effects are primary; these are protoclastic struc- 
tures, due to slight movement during the closing stages of consolida- 
tion of the rock. Uralitization of the pyroxene, interstitial epidote 
and (rarely) tourmaline, marginal granulation of the feldspars, and 
strain, are all of very late magmatic stage; the ore itself, related to 
this period, petrographically exhibits replacement relations to its 
parent rock. 
The Stewart (or Sunk) mine. This mine was the most exten- 
sively developed of the group. The outcrop extends along the east- 
ern flank of a steep hill facing Canopus creek and the workings fol- 
low the magnetite for about 1500 feet along the strike. Between the 
south end of the Canada mine and the north end of the Sunk there 
is an interval of a mile or more in which no openings appear. Active 
