50i W. K Ford— Mineral Notes. 



course it is possible that the base is a cleavage face rather than 

 a natural plane, although the appearance of the face is rather 

 against this possibility. The identity of the mineral was proven 

 by qualitative tests on some very small fragments of the material 

 obtained from another specimen of the same occurrence and 

 kindly given by Mr. Calm for that purpose. 



The second locality that has recently furnished spangolite is 

 the Grand Central Mine, Eureka, Tintic District, Utah. These 

 specimens show very small hexagonal crystals with horizontal 

 striations in the prism-pyramid zone and are of the characteris- 

 tic color. The base is again prominent ; in some cases appar- 

 ently as the natural face and in others as the cleavage plane. 

 The hemimorphic symmetry is not obvious. The crystals 

 occur upon massive limonite and cuprite with traces of an 

 earthy copper mineral, probably chrysocolla. It was impossible 

 to get material from the specimens upon which to make chemi- 

 cal tests, but the appearance and association of the crystals is so 

 characteristic as to leave no doubt as to their identity. It is 

 interesting to note that Miers* pointed out the similarity 

 between the minerals found on the Cornwall specimens and 

 those occurring in the Tintic District, and suggested, there- 

 fore, that the original specimen might have come from that 

 locality. The original specimen, however, is quite distinct in 

 character from either of the occurrences described above. 



Mineralogical Laboratory, Sheffield Scientific School, 

 Yale University, New Haven, Conn. 



* Loc. cit. 



