THE COLLECTION OF MINERALS 



Phosphates, Vanadates, Arsenates, Antimonates, Columbates, 

 Tantalates, Borates, Tungstates, Molybdates, Sulphates, Chro- 

 mates and Nitrates. These are to be found in Desk Cases 20-25 

 and in Wall Case O, but it is impossible in this brief review of the 

 collection to dwell upon the interest and beauty of the many 

 species assembled in this section. 



Prominent among them, on account of the great beauty of 



MALACHITE FROM BISBEE, ARIZONA 



its mineralogical development, is the sulphate of barium, or Barite, 

 (Desk Case 23, Wall Case 0). This is a handsome species not 

 remarkable for crystalline variety, but often grouped in sheaves 

 of radiating plates, frequently massive and banded, occasionally 

 globular, fibrous or granular. The crystals are commonly 

 tabular, somewhat modified on the edges, and frequently are 

 tinged yellow, red, green, blue or brown. Barite is found in 

 metallic veins and is of especially common occurrence in lead 



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