ADIRONDACK MAGNETIC IRON ORES II J 



lished. The geologic relations are obscured by the heavy drift 

 covering the lower slopes of the ridge and the valley floor. The 

 results of magnetic surveys and diamond drill tests, so far as they 

 can be interpreted, indicate the probable interruption of the 

 deposits at a point not much distant from the Burden pit. 



Another group of deposits has been shown to occur, though 

 completely buried beneath drift, on a low ridge 2000 feet west of 

 the main group and is known as the Phillips vein. Its northern 

 extremity lies about 2000 feet northwest of the Burden while 

 its trend is southwest toward the 81 ore body. It consists of 

 two parallel veins which correspond quite closely with the front 

 and back veins of the main group and like them have a north- 

 westerly dip. Their position and similarity of relations suggest 

 the possibility that they are a displaced portion of the main ore 

 zone. The existence of a fault with a throw to the northwest 

 would explain the sudden termination of the ore near the Burden 

 pit and may be considered also not improbable owing to the severe 

 dynamic strains to which the strata have been subjected, as mani- 

 fested by the folding and by the minor flexures and shearing 

 effects that are observable in the adjacent ore bodies and inclosing 

 walls. The indicated throw of the fault is a little west of north, 

 approximately parallel to the axis of the main fold. 



Mining operations are confined at the present time to the southern 

 section of the ore zone. In this part there are some 20 slopes or 

 inclined shafts, besides open cast workings, located at intervals 

 along the outcrop of the front and back veins. Beginning at the 

 southwestern extremity, the first openings 01 the front vein are 

 the Weston and Hamnoni, then follow in order N03. 1, 2, Hall, 

 3, 4, and so on up to No. 16, which is near the old mill. On the 

 back vein are the Burden, Cannon and Dickson pits. 



Most of the ore is now obtains! by underground mining in the 

 Hall slope and the adjacent slopes 3, 4 and 5, and by open-cut 

 workings at the Burden and Cannon pits. The deepest working is 

 No. 4 which has bem carried down to a depth of 1400 f3et on the 

 course of the deposit or about 8 do feet vertically. The Hall and 

 No. 3 slopes have reached nearly equal depth. The dip of the 

 ore bodies in this section is about 45 north at the surface but 

 gradually flattens downward to 25 or less. 



At the Burden and Cannon open cuts the width of the back vein 

 is fully 150 feet measured along the surface. In the bottom of the 

 Hall slope the horizontal drifts are 200 feet wide. Such thick- 

 nesses are unusual, however, and in the former instance may be 



