[Proceedings United States National Museum, 1884. Appendix.] 



SMITHSONIAN INSTITUTION. 



TJ3sria?Er> states isr ation a.l ivl tj s e tt m:. 



No. 31. 



PLAN TO ILLUSTRATE THE MINERAL RESOURCES OF THE UNITED 

 STATES AND THEIR UTILIZATION, AT THE "WORLD'S INDUS- 

 TRIAL AND COTTON CENTENNIAL EXPOSITION OF 1884-1885, 

 AT NEW ORLEANS. 



BY FRED. P. DEWEY, ^ 



Curator of Economic Geology and Metallurgy. 



In the first division of this collection — that of Economic Geology, or 

 the natural occurrence of materials of economic value — it is designed 

 to exhibit collections illustrating the different kinds and grades of the 

 ores of each metal, and also a few collectious of non-metallic minerals 

 of economic importance. 



In the second division — that of Metallurgy — it is designed to exhibit 

 collections representing the processes for the extraction of the metals 

 from their ores by specimens, where practicable, filling the gaps by 

 means of illustrations and descriptions and accompanying them by gen- 

 eral illustrations and descriptions so as to fully explain these processes. 



In making up the ore collection it has been designed to represent all 

 the different varieties of each ore and many of the most prominent min- 

 ing regions, so as to give a good general idea of the nature of the oc- 

 currences of the metals and also their distribution, but it has not been 

 possible to show every occurrence of each variety of an ore, neither has 

 it been possible to represent every mining region. 



The Lake Superior copper region is very thoroughly represented, 

 both on account of the value of the mines of this region and as repre- 

 senting the kind of collections it is desirable for the Museum to possess 

 to illustrate a region or a mine. 



Taking, first, the region, it is represented by three prominent mines 

 showing three different and characteristic- occurrences of th'^ ore. 



First, the so-called Mass mines, which are characterized by the occur- 

 rence of large masses of free copper, amounting in some cases to many 

 tons of metal in a single mass, are represented by the Central mine. 



fll . 617 



