72 TR0N ORES OF IRON SPRINGS DISTRICT, UTAH. 
The samples rim as low as 45 per cent in iron and as high as 69 per 
cent. The hard ore in the andesite runs higher on the average than 
the ore in the limestone. The ore at the surface, with few exceptions, 
has a higher percentage of iron than that below, the difference ranging 
from 3 to 12 per cent. ' 
Phosphorus may diminish slightly in the deepest explorations, that 
is, below about 100 feet, but the distribution is so irregular and 
capricious that this generalization is doubtful. There are common 
variations within a short distance, both vertical and horizontal, of 
0.050 to 3.18 per cent. A few 10-foot samples of ore run below the 
Bessemer limit in phosphorus, but practically all the ore as mined will 
be non-Bessemer ore. 
Sdica, averaging about 7 per cent, varies between 2 and 28 per cent, 
the lower figures being more common in the ore in the andesite. 
There is a distinct loss of silica at the surface, amounting to about 
4 per cent as compared with that immediately below the surface. 
Lime and magnesia range from 1.5 to 11 per cent. The hard ores 
in the andesite carry slightly less than the soft ores in the limestone. 
In both types the deeper ores carry the higher percentage. While 
both silica and lime are in greater quantity below the surface, cor- 
responding to a lower percentage of iron, the lime and magnesia 
increase relatively faster than the silica with depth. Whereas at 
the surface a common ratio of silica to calcium and magnesium oxides 
is 2 to 1 by weight; below the surface it is more nearly 1 to 1. 
Combined water varies from less than 1 per cent in the magnetite 
to 4 per cent in the soft ores, averaging about 3 per cent. One 
determination of moisture in crystallized magnetite a gives 0.45 per 
cent after heating to 110° C. 
Sulphur is present in variable amounts, averaging .057 per cent, 
but in the deep exploration of one of the deposits, the Duncan, this 
figure is exceeded and the presence of sulphur becomes a serious 
consideration. There seems to be no general evidence of increase 
with depth, so far as exploration has yet gone, but water level has 
not yet been reached in the explorations. 
Copper, titanium, and manganese are present, but not in injurious 
amounts. 
Soda and potassa are determined in a single specimen. 6 Their 
significance is discussed on page 77. 
PI. XX summarizes the available information in regard to the 
variation of composition with depth. 
A comparison of average analyses of Iron Springs iron ores with 
Lake Superior hematites and with the Clinton hematites of Alabama 
is made in the following table: 
a Specimen 46113, Lindsay Hill. Analysis by R. D. Hall, University of Wisconsin. 
P Specimen 46333A, Lindsay Hill. Analysis by R. D. Hall, University of Wisconsin 
