74 IRON ORES OF IRON SPRINGS DISTRICT, UTAH. 
requirements, but partly to show up the ore bodies. Some of the 
more vigorous exploration was conducted during the years 1902 
and 1903. The total number of pits sunk to date has been approxi- 
mately 1 ,600, of which 30 have gone to a depth greater than 50 feet. 
The maximum depth has been 130 feet. 
Diamond drills have been used only at the Desert Mound, where 
5 holes have been sunk. The detailed results of this drilling have 
been withheld from the United States Geological Survey, though 
some of the cores have been examined. 
