CRYSTAL FORMS OF CALCITE FROM JOPLIN, 
MISSOURI. 
Large crystals of calcite from Joplin, Missouri, have been knowm 
for some years to collectors, and have become widely distributed im 
collections. The crystals are remarkable, not only for their size, 
but for their transparency, varied color and the perfection of their 
crystal form. So far as I can learn no crystallographic study of 
these calcites has ever been published. Photographs of some of 
the crystals, together with some general statements as to the occur- 
rence of calcite in Missouri, are to be found on pp. 457-9 of Vol. 
VII, of the Reports of the Missouri Geological Survey. There is. 
also mention, on p. 567 of the same volume, of calcite crystals of 
large size occurring in Crystal Cave, Joplin, and some description 
of the cave is given. No crystallographic details are given in this. 
account, however, the crystals being simply described as scaleno- 
hedral or rhombohedral. The present study of some of the crystal 
forms can in no sense be considered a complete one, since the only 
material undertaken to be described is that comprised in the Mu- 
seum collections, and some crystals that were kindly loaned for 
examination, through Prof. J. P. Iddings, by the University of Chi- 
cago. Having, however, cursorily examined a large number of 
crystals from this locality as exhibited in collections, both in this 
country and in Europe, I may say that I have found them to be 
remarkably uniform in character, and hence believe the character- 
istic forms to be largely comprised in the types here described. 
The specimens in the Museum collection have been obtained from 
various sources, chiefly by purchase or exchange, but some were 
collected at the mines in Joplin during the spring of 1898 by Mr. 
H. W. Nichols, Assistant Curator of Geology. 
LOGALITTIES JOR LARGE GRY olALS: 
The large crystals known to collectors are chiefly of two types,. 
differing in color and form. ‘Those of the type which I may desig- 
nate as Type No. 1 are characterized by a delicate violet to wine 
yellow color, often showing within a deeper yellow or violet light. 
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