134 NEW YORK STATE MUSEUM 
AMsld, HOG WISIUN| (OV ALSCOUNSIDVAIL ID, ILIA NW IES (COMIN TENG, IN, WC 
BY NELSON C. DALE 
Introduction 
Grateful acknowledgements are due Dr John M. Clarke, Direc- 
tor of the New York State Museum, for the opportunity of 
investigating this most interesting vein occurrence, also to Dr. C. H. 
Smyth of Princeton University for his very helpful suggestions 
and to Messrs G. M. Coram and G. M. Hayes of Utica, N. Y., for 
their loan of some excellent specimens which have helped to illus- 
trate this report. 
Location 
About a mile from the mouth of Fall brook, a tributary of the 
Black river in the township of Lyonsdale, N. Y., is an interesting 
spot known to the inhabitants of that vicinity as the “old silver 
mine.” As no evidence of the former silver mining can be seen 
besides what is left of the foundations of the old smelter and 
some effects of water control and not a trace of the customary 
mine dump, it is generally concluded that through floodings and 
the effects of river erosion most of the records of this activity 
which was concluded in the eighties have been swept away or 
concealed. | 
Our interest.at present is centered about the peculiar vein fill- 
ings uncovered on the north bank of the stream for about 4o feet 
by the owners of the property, who have been interested in the 
occurrence of the box structure and of chalcopyrite. The former 
term, refers to the many and varied hollow pseudocrystal forms of 
crystalline quartz, an unusual sort of cellular breccia structure. 
General Description of the Vein 
The vein in which these peculiar forms, known by the collectors 
as “boxes,” occur is characterized by a remarkable platy and 
cellular development, the plates or bands of which consist of 
crystalline quartz and brownish pink manganiferous calcite. 
There are parts of the vein where carbonate and quartz bands 
alternate with each other, typical of the banded structures; other 
parts where comb structures of crystalline quartz are found com- 
bined with banded zones and still others in which there is a notice- 
able cellular structure, but generally these features are found in 
close association with each other The most noticeable features 
