WINONA COUNTY. 267 



Minerals.] 



ton exhumed several years ago from a mound situated on the high loam- 

 terrace of the Mississippi, near the same place. From the latter mound 

 were taken several skulls and other human bones, a lot of flint arrow-points, 

 and one copper hatchet, the edge of which was said to have been hardened 

 by some process. 



Minerals. An impure limonite, pseudomorphous after marcasite, is 

 frequently seen lying loosely on the tops of the wind-worn bluffs along 

 the Mississippi, among other fragments of siliceous rock and of quartz. 

 Sometimes it is in cock's-comb aggregations, and sometimes irregularly 

 spreading and hepatic in outline, or botryoidal or mammillated. It seems 

 to be mainly at the bottom of the debris covering the rock. 



At St. Charles was formerly a large piece of lamellar calcite, very dense 

 and firm,* lying on a sloping surface underlain by the St. Peter sandstone. 



It was originally four or five feet across, and about a foot thick, but has 







been broken up for hand specimens and carried away. It very nearly re- 

 sembled argentine and had a wavy and curly internal structure, in layers, 

 giving it much the appearance of woody fiber, and it was regarded as a 

 specimen of petrified wood for a number of years after its discovery. 



FIG. 14. PROFILE ROCK, WINONA. 



See the Houston county report for an account of similar deposits in that county. 



