Fig. 1 Ore from breast of incline, Tower mine 
Fig. 2 Ore from lower Shaft-Standish mine. 
Fig. 3. Ore from 3700 foot level Forest of Dean mine. 
Fig. 4 Ore from Bull mine. 
Ordinary light, X 35. Magnetite (black areas) is replacing Pochuck- 
Grenville in the Tower (fig. 1), Forest of Dean (fig. 3) and Bull (fig. 4). 
The rough grayish mineral in fig. 2 (Standish mine) is garnet, mixed 
with calcite, and the white clear areas are quartz. Evidently a more or less 
calcareous phase of the Grenville has been replaced in the Standish ore. The 
nonmetallic areas shown in fig. 4 (Bull) are remnants of green pyroxene. 
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