Hearst Mine, Shannon County, Missouri, USAi

Regional Level Types
Hearst Mine	Mine
Shannon County	County
Missouri	State
USA	Country

This mine is located 2 1/2 miles east of Winona. It consists mainly of an open cut 150 feet long and 50 to 60 feet wide, which was made upon a small outcrop of brown ore located upon the southeast slope of a prominent hill. The west face of this pit consists almost entirely of barren, residual clay, and flint, with a broken bed of quartzose sandstone 12 to 18 inches thick lying in an uneven but well defined line slightly above the middle of the face, but dropping abruptly to near its base at the north end. The east face shows some brown ore in clay but no sandstone. Forty to 50 feet of the north face shows considerable hard brown and soft red ore occurring in veins and seams pitching rather uniformly about 35° west of north.

The red ore is soft and greasy and is associated with a fine, ocherous clay which in places is replaced laterally by a seam of soft yellow sand. At the base of the north face, the ore lies both above and below a 12 inch layer of quartzose sand and chert breccia which resembles the sandstone ledge in the west face described above.

In the extreme northeast corner of the cut a small heading encountered streaks of soft red ore varying from 12 to 20 inches in thickness mixed with seams of clay, all of which pitch to the northwest.

A 40 foot shaft near the north end of the cut is reported to be in ore mixed with some sand throughout its entire depth. From the foot of this shaft a drift has been driven 15 feet to the north. The west face of this drift carries very little ore, while the east face shows seams of soft red and hard brown ore which dip to the northwest.

A 15 foot shaft, located on the east bank of the cut, encountered, throughout the lower 12 feet, pitching seams of red ore mixed with seams of white, yellow, and red clay and soft white sand. A 30 foot drift, extending south 35° west from the bottom of this shaft, shows pitching seams of similar material throughout its length. A 15 foot drift, extending north 55° west from the same point, encountered red ore in the back and developed an 18 inch seam of ore at the foot of the shaft pitching in the direction of the drift. Another shaft, about 30 feet south of the last, is reported to have encountered similar material, having the same general northwest dip.

From the foregoing, it would appear that this deposit of red and brown hematite occurs along a zone of breeciation or faulting, or some sort of sink structure, the degree or exact nature of which has not been determined. Since the hills in this vicinity arc everywhere thickly covered with a mantle of residuum, mining developments alone will disclose the factors controlling the extent of the ore body. The facts so far developed suggest that a northeast-southwest zone of brecciation cuts the large pit near the point where the 40 foot shaft is now sunk, and that the red ore will be confined to a belt on the east and conform closely to such a line.

The ore is secondary after iron sulphites, and shows sulphide pseudomorphs. It is partly red and partly brown, but in the absence of more definite knowledge regarding the accompanying structures, it is classed as a secondary limonite deposit.

This property was opened during 1902 and 1903, after which operations ceased until the fall of 1909. An early shipment ran 53.15% iron, 11.93% silica, 0.103% P hos., 0.06% Mn., and 7.30% moisture.

The ore was hauled three miles by wagon and placed on board cars at Low Wossie for 75 cts. per ton. Three hundred and fifty tons were produced.