188 



REPORT OF NATIONAL MUSEUM, 1899. 



very constantly associated with tlie ores of niclvel (niccolite, millerite, 

 chloanthite, etc.), and is obtained as a by-product in smelting. Con- 

 siderable quantities have thus from time to time been obtained from 

 the Gap mines of Pennsylvania, Mine La Motte, Missouri, and Love- 

 lock, Nevada. (Specimen No. 61324, U.S.N.M.) The nickel mines of 

 New Caledonia are perhaps the most productive. The ore here (a sili- 

 cate), carries some 3 per cent of cobalt protoxide. (Specimen No. 

 61027, U.S.N.M.) 



A vein of cobalt ore near Gothic, Gunnison County, Colorado, is 

 descrilwd as lying in granite, the gangue material being mainl}^ cal- 

 cite, throughout which was disseminated the ore in the form of 

 smaltite. With it were associated erythrite, a small amount of iron 

 pyrites, and native silver. An analysis of this ore yielded as below: 



Cobalt 11.59 



Iron 11. 99 



Arsenic 63. 82 



Silii-a 2. 60 



Lead 2. 05 



Sulphur 1. 55 



Bismuth 1. 13 



Copper 0. 16 



Nickel Trace. 



Silver Trace. 



94. 89 



A cobalt ore, consisting of a mixture of glaucodot and erythrite, 

 occurring near Carcoar Railway Station, New South Wales, has the 

 composition given below: 



Constituents. 



Moisture 



Metallic arsenic 



Metallic cobalt 



Metallic nickel 



Metallic iron 



Alumina 



Metallic manganese 



Metallic calcium 



Magnesium 



Gold 



Silver 



Sulphur 



Gangue (insoluble in acids). 



Specific gravity 



.120 

 51.810 

 10. 447 



.590 

 11.860 



Nil. 



Nil. 



1.480 



Trace. 



Trace. 



1.520 



22. 078 



99. 905 

 5.43 



2.180 

 29.010 

 13. 830 



.390 

 15.78 

 Trace. 



Nil. 



.71 



11. 24 

 26.31 



According to the Annual Report, Department of Mines, for 1888, 

 this ore occurs concentrated in irregular hollows and bunches, often 

 intimately mixed w ith diorite in a line of fissure between an intrusive 

 diorite and slate, the lissure running for some distance following the 

 line of junction between the two rocks, and being presumably formed 

 at the time of the extrusion of the diorite. 



