Troost on the Pyroxene. 
59 
we shall proceed to give an account of the different species 
that have been formed from this family. We will call them 
Volcanic Pyroxene. 
t^ugite — — " m 
Coccolite 
Sahlite 
Baikalite 
Fassaite 
Sherzolite • 
Diopside 
Mussite ' 
White 
1. Volcanic P.* It occurs in small and moderately sized 
regular crystals, or in grains which are sometimes insula- 
ted or sometimes combined and dispersed, or disseminated 
through lava or rocks. Different analyses have been made 
of it. — It is composed 
^te^, 
Etna. 
Vauquel. 
52.50 
Frascati. 
Klaproth. 
48 
Rhinberg, 
Klaproth. 
52 
Magnesia, 
Alumine, 
10 
3.30 
8.75 
5 
12.75 
5.75 
Lime, 
13.20 
24 
14 
Iron, 
14.66 
12 
12.25 
Manganese, 
Potash, 
2 
0 
1 
trace 
0.25 
0 
Water, 
0 
0 
0.25 
Loss, 
4 
0 
0 
Tromsdorf found in the Pyroxene of the Etna 5. 18 pot- 
ash. Klaproth detected also a small quantity in those of 
* Schorl noir en prisme octaedre Rome de L. Schorl volcanique, 
Bergm. Folcanite and Virescite, Lamethrie. Augite^ Werner. Augite., 
Jameson. 
I 
