4^ DESCRIPTIVE MINERALOGY. 



4.70 to 4.80. Before the blowpipe, fuses on the edges. Composed of oxide of manganese 

 75.80, silica 13.17, oxide of iron 4.14, alumina 2.80. 

 At Lebanon in Pennsylvania. 



CALAMINE. 

 Carbonate of Zinc. Cleaveland and PAiUips. 



Colour greyish or yellowish. Crystallized, compact and earthy. Primary an obtuse 

 rhombohedron of 107° 40'. Lustre between vitreous and pearly. Hardness 5.0. Sp.gr. 

 4.20 to 4.50. Infusiblg. before the blowpipe. Composed of oxide of zinc 64.80, carbonic 

 acid 35.20. 



Brookfield, Connecticut ; Franklin, New- Jersey ; Perkiomen, Pennsylvania ; and at the 

 lead mines in Missouri. 



CHLOROPHiEITE. 



Chlorophaeitc. MacCuUoch and Cleaveland. 



Colour, when recently broken, from the transparent green of chrysolite, to the dull muddy 

 green of steatite ; when exposed for a few hours, it turns darker, and at length becomes 

 black. Occurs in nodules, often round, and varying in size. Soft. Brittle. Sp. gr. 2.02. 

 Before the blowpipe, it remains unchanged. Composed principally of silica and iron, with a 

 httle alumina. 



This mineral, which occurs in Scotland and Iceland in amygdaloid, has also been found 

 at Gill in Massachusetts, Southbury in Connecticut, and elsewhere in the United States. It 

 is, however, still a doubtful species, 



CHLOROPHYLLITE.* 



Colour green. In tabular or short six-sided prisms arranged in folia or in columnar masses, 

 resulting from the openness of natural joints. Cleaves into regular six-sided prisms with 

 resplendent surfaces. Harder than apatite. Sp. gr. 2.70. Before the blowpipe, is glazed 

 on the surface, but is not entirely fused. Composed of silica 45.20, phosphate of alumina 

 27.60, magnesia 9.60, protoxide of iron 8.26, manganese 4.10, water 3.60, traces of 

 potash and loss 1 . 64. 



Unity, New-Hampshire. 



* C. T. Jackson. Report on the Geology of Nm-Hampthire, 1841. 



