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 Q, 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 
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MALACHITE FROM BISBEE, ARIZONA 
its mineralogical development, is the sulphate of barium, or Barite, 
(Desk Case 23, Wall Case Q). 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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