APPENDIX. 329 



PYROSKLERITE. 



Massive. Cleavage parallel with the faces of a rhombic prism. 

 Fracture uneven arid splintery. Lustre on the cleavage faces feebly 

 pearly, in other directions it is dull. Color, apple-green to light green- 

 ish grey. Hardness between 2-5 and 3-5. Sp. gr. =2-74. Streak 

 white. 



1. Before the blow-pipe it fuses with difficulty into a greyish glass. 

 With borax, it slowly yields a glass colored by chrome. It is decompo- 

 sed, when in the state of powder by concentrated sulphuric acid. 



2. Analysis. 



By KOBELI,. 



Silica . . . ' . . . . 37-03 



Alumina 13-50 



Magnesia 31-62 



Protoxide of iron 3-52 



Green oxide of chrome T43 



Water 11-00 



3- It occurs at Elba with Chonikrite. It seems to be closely rela- 

 ted to Picrolite. 



RAPHYLLILE. (See Hornblende.) 

 RETINALITE. (See Serpentine.) 



RHOMB SPAR. (See Vol. II, p. 164.) 



Analysis. 

 By STROMEYER. 



Magnesia . 41-06 . . . 42-40 



Protoxide of iron . 8-57 . . . 7-47 



Oxide of manganese . 0-43 . . . 0-62 



Carbonic acid . 48-94 . . . 49-67 



SASSOLIN. (See Vol. II, p. 171.) 



The deposit of this mineral occurs within the crater of Volcano, one of 

 the Lipari Islands, where it forms thin coatings on the surface of sul- 

 phur, and around the openings, whence the subterranean exhalations 

 are discharged. The variety deposited by the lagunes of Tuscany and 

 the hot-springs of Sasso is of a greyer color, and harder than that from 

 Volcano. According to KLAPROTH, it contains 11 p. c. of sulphate of 

 magnesia, and 3 p. c. of sulphate of lime. 



