60 FLUORSPAR DEPOSITS OF SOUTHERN ILLINOIS, [bull. 255. 



given high angles of dip. A number of prospect shafts have shown 

 some brecciation of the rock and the presence of calcite as a cementing 

 materiaL 



Golconda prospects. — About a mile south of Golconda, on the 

 river bank, faulting has brought the Mansfield sandstone of the bluffs 

 into contact with the Chester formations. Parallel to the fault the 

 sandstone is sheeted or sheared and a minor amount of barite has been 

 introduced. No other minerals occur. 



West of Golconda the Chester comes in abruptly, replacing the 

 ]\Iansfield, and there seem to be several minor parallel faults and 

 crevices. In one of the latter, showing in the first railway cut west 

 of the toAvn, is the Gilbert dike, which was prospected for mineral to 

 a depth of 70 feet in 1003 without favorable results. 



Bay City mine. — Near Bay City the rocks are broken by fault 

 planes presumed to represent the Kosiclare-Fairview system of fault- 

 ing. Along these planes fluorite, galena, and blende have l)een de- 

 posited, and an effort is being made to mine them. The Black mine 

 is located in section 26, T. 14 S., E. 6 E,, on a low hill rising about 

 25 feet above the Ohio River bottom land and cut off from the main 

 bluff by a low col. Near the old shaft there are clear evidences of 

 faulting in the sandstone which forms the surface material. The 

 dump shows a brecciated limestone cemented by calcite and fluorite 

 and carr3dng galena and blende. A small amount of zinc carbonate- 

 also occurs. The vein dips to the west, and a new" shaft was being 

 sunk to intersect it. In the hillside near by there is a narrow belt 

 of limestone running about parallel wdth the fault upon which the 

 ore has been found. 



MINES IN SALINE COUNTY. 



General relations. — Near the southern border of Saline County, not 

 far from the Pope County line, small quantities of galena and fluorite 

 have ])een found and some prospecting is going on. The country is 

 rugged, the area including a part of Karbers liidge. The rocks con- 

 sist mainly of Mansfield sandstone, with subordinate areas of the 

 later coal measures and some infaulted blocks of Chester limestone. 



Khuj and Fergusen mine. — This property is in section 21, T. 10 S., 

 R. 7 E. The surface rocks consist mainly of sandstone, with subor- 

 dinate amounts of black shale and limestone. They have been con- 

 siderably disturbed and dip occasionally at high angles. There are 

 three shafts. At the first the beds strike nearly north and south 

 and dip 52° to the east. This shaft has been sunk on a thin bed of 

 black shale, and there is apparently no displacement, though a minor 

 amount of dip faulting may be present. Barite and fluorite are 

 found in small amounts crystallized together in broken quartzitic 



