BARITE IN LEAD AND ZINC DISTRICT 
237 
THE OCCURRENCE OF BARITE IN THE LEAD AND ZINC 
DISTRICT OP IOWA, ILLINOIS AND WISCONSIN. 
W. D. SHIPTON. 
INTRODUCTION. 
According to the reports of the Iowa, Illinois, and Wisconsin 
Geological Surveys natural crystals of barite are found rarely 
in the Lead and Zinc District of Iowa, Illinois, and Wisconsin. 
On account of the rarity of distinct crystals, considerable inter- 
est attaches to the finding of these crystals in this region at 
Hanover, Illinois. In the possession of Mr. T. D. Shipton of 
Hanover, are sixty or more well defined crystals of barite ; it 
is to him that the writer is indebted for the material from which 
this paper was prepared. 
OCOURRENOE. 
Keyes refers to barite as commonly associated with the lead 
and zinc ores in the Dubuque region. He reports good crystalli- 
zation of tabular form, and bluish tints as of not infrequent 
occurrence.^ White refers to barite as having been found only 
in minute quantities in Iowa. It was detected in the lead caves 
of Duhuque.^ Cox reports that no well defined crystals have 
been found in the lead and zinc district of Illinois, although 
barite has been found at all horizons from the bottom of the 
oil rock to the top of the Maquoketa shale.^ Henry W. Nichols, 
Assistant Curator of Geology in the Field Museum, Chicago, re- 
ports these crystals from Hanoyer as being the first that he had 
ever seen from the state of Illinois. According to Volume I, 
page 213, of the Wisconsin Geological Survey, barite or heavy- 
spar is found occasionally with calcite in the lead-bearing crev- 
ices; but only a small amount of this mineral has ever been 
found, and there are comparatively few places where it occurs 
at all. At one locality, near Scales Mound in Illinois, in a posi- 
tion where no lead has been found, and at the very summit of 
the Galena limestone, there is a thin bed of dolomite with nu- 
merous geodic cavities in which, in connection with pyrites and 
ilowa Geological Survey, Volume I, page 194. 
Uowa, Geology of, Volume II, 1870, page 305, 
Illinois Geological Survey, Bulletin 21, page 38. 
