THE MINERALS OF IDAHO 



By Earl V. Shannon 



Assistant Curator of Geology, United States National Museum 



INTRODUCTION 



The present volume contains the results of a comparatively large 

 amount of detailed work, principally upon the specimens of Idaho 

 ores and minerals in the United States National Museum. To- 

 gether with these original observations is given a very complete 

 compilation of such literature as pertains to the mineralogy of the 

 State. 



No such work on the minerals of a geographic area can be complete 

 and there are doubless many occurrences of unusual minerals in the 

 State, of which the writer has no knowledge. New discoveries 

 will doubtless be made with increasing number from year to year and 

 the present manuscript, however carefully compiled, can serve only 

 as a nucleus around which to assemble new facts. 



No visits to the state on observation or collecting trips have been 

 possible since the work was begun. The writer spent many years as 

 a collector in the Coeur d'Alene district and the statements regard- 

 ing the occurrence of the minerals of that district are based upon 

 personal observation. It has not been possible to visit this region 

 within the past several years or at any time since training was 

 acquired in the recognition of obscure or unusual minerals. 



The specimens preserved in the National Museum have, for the 

 most part, been random selections of typical ores or specimens 

 selected to illustrate some geologic phenomenon without particular 

 reference to the mineralogy and such unusual minerals as they contain 

 are nearly wholly accidental. In cases where mineral occurrences 

 have not been mentioned, the excuse must be that no specimen was 

 available for examination. 



Many remarkably fine specimens have been lost through smelting 

 or otherwise and the occurrence of many minerals in abundance in 

 rich ores is now established only by fragmentary records substan- 

 tiated by a single specimen accidentally preserved. It is hoped that 

 one purpose of this publication will be accomplished by arousing 

 interest of persons possessing a latent interest in mineralogy in the 

 preservation of unusual mineral specimens. It has not been possible, 

 during the preparation of this report, to establish connections with a 

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