THE IRON ORES OF THE IRON SPRINGS DISTRICT OF 
SOUTHERN UTAH. 
By Charles Kenneth Leith and Edmund Cecil Harder. 
CHAPTER I. 
INTRODUCTION. 
PURPOSE OF THE INVESTIGATION. 
The enormous and rapidly increasing consumption of iron ore in 
the United States during the last few years has led to careful inven- 
tories of available supplies, both in producing districts and in rela- 
tively unknown fields, with the result in general of emphasizing the 
limitation of the deposits now worked and of pointing out the necessity 
for the early exploitation of new ones.. Up to the present time less 
than 2 per cent of the iron ore mined annually has come from west 
of Mississippi River, but there have long been known in that region 
large deposits of iron ore which have not been exploited because of 
lack of transportation facilities or distance from consuming centers. 
The part these deposits are to play in meeting the future demand for 
iron ore, the possibilities or probabilities of finding other large deposits 
in the West, and the o-eoloo;ical features of significance in connection 
with these questions remain largely to be ascertained. 
Mr. Leith began a general geological reconnaissance, of western 
iron ores in 1903 and continued it during 1904, 1905, and 1906, visiting 
some of the better known ore deposits of Utah, Colorado, Wyoming, 
Washington, British Columbia, California, and Missouri. It early 
became apparent to him, as it had been apparent to others, that the 
iron-ore deposits of the West are prevailingly of a distinct and uniform 
type — an irregular replacement of limestone near the contact with 
igneous rocks, or a vein filling in both limestone and igneous rock — a 
type fundamentally different from that of the important producing 
districts east of Mississippi River, and probably of different origin. 
The deposits of the Iron Springs district of southern Utah were 
selected as typical of this class of deposits, well located for study, and 
of such size and quality as to warrant the belief that their exploitation 
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