244 J\futtalPs Geological and Mineralogical Remarks. 



sionally in octahedrons, and minute pale bluish green pris- 

 matic and translucent crystals, which are probably phos- 

 phate of lime. These veins, which stand up in crests from 

 the more decomposable carbonate of lime in which they 

 are imbedded, present also on the surface druses of augite 

 crystals, and some of the accompanying minerals. 



A little distance from this vein, there is another, appa- 

 rently much broader in its dimensions, being a mixture in 

 the mass, more or less intimate so as to be often minutely 

 granular, of green felspar of a colour from pale olive to 

 that of carbonate of copper, black hornblende, gray quartz, 

 whitish augite, mica, and occasionally sphene or silico-cal- 

 careous oxyd of titanium. In the cavities of this vein, and 

 often considerably immersed below the surface, are, in con- 

 siderable abundance, bluish green octahedrons of the spin- 

 elle, sometimes presenting truncations on the edges, but 

 more commonly on the common base, and occasionally exhi- 

 biting cuneiform summits. The angle of coincidence of its 

 faces measured on the reflecting goniometer, by my friend 

 Dr. Torrey, are 109.23 ; it likewise scratches quartz, is in- 

 fusible, and scarcely becomes paler by heat. The crystals 

 are in size from the bigness of a pin's head to half an inch 

 in length, the larger of course, darker, and mostly break- 

 ing into splintery fragments, have internally a more or less 

 perfectly conchoidal fracture, and high resinous lustre: 

 most of the crystals, when slightly rubbed, indeed, present 

 the brilliance of polished steel; the smaller crystals are 

 also so far translucent as to reflect a splendid coloured re- 

 flection, little short of that of the diamond. In these cavi- 

 ties they are commonly associated with augite crystals, 

 quartz, hornblende, green felspar, crystals of phosphate of 

 lime, and in two or three of my specimens imbedded mi- 

 ca, arsenical pyrites, and traces of galena. The aflinity 

 which these specimens bear to those of Vesuvius, contain- 

 ing Ceylanite is striking to astonishment, and I have even 

 seen the brucite or condrodite, like that of Sparta, from 

 Vesuvius.* No vestige of volcanic fires, more than the 



* In the cabinet of Mr. Wagner, junior, Philadelphia. Since writing 

 the above, my friend Mr. Bowen, subjected another fragment of the sup- 

 posed condrodite of Vesuvius which belongs to the cabinet at New-Ha- 

 ven, to examination, and found it to agree in the general results, with the 

 analysis of that mineral recently published in Europe. It is now also 

 found in one or two other localities in the United States besides Spaifa. 



