280 Gustav Rose on Greenstone and [Oct. 



is a large portion of iron regulus, with many perfect crystals 

 of titanium interspersed through it. Small iron reguli, 

 with titanium, appear on the surface and sides. 



Hypersthene rock occurs in Ural, in scarcely distinct 

 varieties, and also in rolled masses, in the platinum sand 

 of Nischne Tagilsk. To the known, coarse granular 

 varieties, the hypersthene rock of Paul's Island on the 

 coast of Labrador, belongs ; from which locality, both the 

 constituents of the rocks were first made known. The 

 hypersthene found there is characterized by its metallic, 

 almost copper- red, pearly lustre ; the labradorite is grayish- 

 white, very translucent, and has a frequent display of co- 

 lours. This hypersthene rock contains no accidental 

 constituents. 



The hypersthene rock of Penig, in Saxony, is also coarsely 

 granular ; the labradorite is transparent ; the hypersthene 

 has a metallic, pearly lustre, and frequently is bordered by 

 hornblende. Somewhat less coarsely granular is the hy- 

 persthene rock of Buchau, at Neurode, in Silesia, the labra- 

 dorite being frequently very translucent, and the hypers- 

 thene brown. The hypersthene rock of Elfdalen consists 

 of similarly equal sized grains ; the labradorite is white, 

 and slightly translucent ; the hypersthene blackish brown. 

 It contains much titaniate of iron, and besides, some olivine 

 and fine needles of apatite. 



At Elfdalen it is worked into vases, often of considerable 

 size, and other ornaments. For the fine polish of which 

 this stone is susceptible, and the contrast of the colours of 

 its constituents, it is scarcely surpassed by any known sub- 

 stance. Many varieties of hypersthene rocks, among the 

 rolled masses, near Berlin, are similar to the Elfdalen rock ; 

 the labradorite is, however, more translucent and some- 

 what greenish coloured ; the hypersthene, slightly dark, 

 but very splendent. It contains titaniate of iron as well as 

 olivine. Other varieties have blacker hypersthene, and 

 are frequently bordered by hornblende. 



The hypersthene rock of Mongon, at Fassa, in Tyrol, 

 occurs frequently in coarsely granular varieties. It consists 

 of white, slightly translucent labradorite, and brown hy- 

 persthene ; the first is predominant, and the hypersthene 



