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NATURAL SCIENCES OF PHILADELPHIA 



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covered there, it was still with considerable surprise to the writer 

 that the material described here proved to be celestite, SrS0 4 . 

 The specimen consists of part of a vein of pink rhodochrosite 

 on a mass of calcite through which is disseminated much franklinite. 

 The rhodochrosite, which is quite crystalline, is filled with solution 

 cavities which are coated with druses of brilliant colorless crystals, 

 rarely over 1 mm. in size. The mineral was found to be biaxial, 

 positive; * = 1.621, £ = 1.625, T = 1.631; all ± .003. A single 

 crystal was measured with the results given in Table III. The 

 habit of the crystal measured is shown in fig. 2; other crystals 

 were tabular parallel to c (001). 



Table III. Celestite, Franklin, N. J. 



Calcite 

 The calcite occurs as a cavity lining on a calcite-zincite mixture 



Fig. 7. Calcite, Fianklin. N. J. 



