)V, ) 
FOREIGN SCIENCE AND THE ARTS. 
EMBRACING MINERALOGY, GEOLOGY, NATURAL HISTORY, 
PHYSICS. &c. 
MINERALOGY. 
PLAGIONrf E.-Tiie crystals of this 
mineral belong to the obliqae rectangular 
prismatic system of Beudant. If we consider 
the faces belonging to an octahedron for the 
punvictur form, then the faces parallel to the 
plane of the two axes are trnncatures of the 
anterior angles. They are implanted in 
quartz. Fracture conchoidal. G. Rose has 
termed it plagionite, from (^jfXayw^ obli- 
que) in consequence of the oblique form and 
inclination of the axis, which measures 107^ 
32'. It consists, accordinor to Rose of Lead 
40‘..52 Antimony 37.94 Sulphur 21.53, Total 
99,99. 
Besides simple sulphuret of antimony, in 
the Wolfsberg antiraonial veins, there are a 
great many combinations of sulphuret of anti- 
mony and sulphuret of lead in ditferent pro- 
portions, viz ; zinkenite, 3 Sb. su. “L Pb. su. 
Plagionite, and Federerz, Bournonite. The; 
two first have only been found at Wolfsberg. 
f Poggeiidorjf, xxviii. 421 .) 
16. NATIVE LITHARGE has been found 
half way up the volcanoes of Popocatepetl 
and Iztacictualt in Mexico, corresponding 
exactly in appearance and composition with 
that derived from the lead furnaces, (Ann, 
des. Mines, vi,) 
17. ARSENICAL PYRITES has been 
analyzed by E. Hoflinann from four locali- 
ties : 
Schnee- 
berg. 
Slaclming. 
Hartz. 
Reichen- 
stein. 
Sulphur . . 
0.14 
5.20 
1 1 .05 
1.94 
Copper . . 
0..50 
99 
99 
Bismuth . . 
2.19 
60.41 
65.99 
Arsenic . . 
71.30 
.53.60 
Nickel . . . 
28.14 
13.37 
30.02 
99 
Cobalt .... 
,, 
5.10 
0,56 
28.8 
Iron 
,, 
13.49 
3.29 
Serpentine 
2.17 
102'27 
97.57 
98..52 
98.18 
the Uralian Mountains, in limestone, where it 
is accompanied with vauquelinite, phosphate 
of lead, quartz, and galena ; colour between 
cochineal and hyacinth ; compact ; crystals, 
rhomboidal prisms, with two large faces, 
which gives them a tabular appearance ; 
edges, translucent ; streak, brick-red ; sp. gr. 
5 75. Before the blowpipe fuses easily into 
a brown mass, which assumes a crystalline 
structure on cooling. In the reducing flame it 
is converted into oxide of chromium and 
metallic lead. It consists of Oxide of lead 
7o.36 Chromic acid 23.61, Total 100.00. 
It is obviously, therefore a subsesqui-chro- 
mate of lead. ( Poggendorjf, xxviii.) 
21. CHROME IRON ORE, from Balti- 
more, was found by Abich to contain, (Pog- 
gendorff, 1831.) 
Silica 
Crystallized. 
AmorpliouJ 
00.83 
Alumina 
... 11.85 
13.85 
Oxide of chromium 
.. 60.04 
51,91 
Protoxide of iron.. 
... 20.13 
18.97 
Magnesia 
9.96 
Total 
. . 99.47 
98.52 
22. WHITE ARSENI ATE OF IRON,— 
Kersten found a specimen of this mineral 
from Freiberg, to consist of Arseniate of iron, 
70,70, Water, 23.50, Total 99.20. (Schweig- 
qer Seidel’s Jahrhuch, vi. 182.) 
23. POLYBASITE. — H. Rose has ana- 
lyzed this mineral from the following locali- 
ties 
Guarisamny, 
Mexico. Scliemnitz. Freiberg. 
Sulphur 17.04 
Antimony . 5.09 
Arsenic 3.74 
Silver 64.29 
Copper. . 
Iron. . . . 
Zinc. . . . 
9.93 
0.06 
0.00 
16.83 
0,25 
6.23 
72.43 
3,04 
0.33 
0.59 
16.35 
8.39 
1.17 
69,99 
4.11 
0,29 
0.00 
18. ARSENIC GLANCE.-Karsten found 
the composition of a specimen from Marien- 
berg, in Saxony Arsenic 93.785 Bismuth 3.0 tl 
Total 99.786. (ScJiiveig. xxiii. 390.1 
19, STERNBERGitE.-Zippa finds this 
composed of Silver 33.2 Iron 36.0 Suh)hur 
30.0, Total 99,2, equivalent to 4 F Su. + Ag. 
Su. (Poggendorff) Ann. xxvii.) 
20 M ELAN OCHROITE.— This mineral 
is found in the neighbourhood of Bere.sow, in 
Total.... 100.15 99.70 100.30 
(Poggendorjf, xxviii. 156.) 
24. VOLTZITE — This mineral is found 
at Pont Gibaud, in Puy de Dome, It pos- 
sesses a pearly lustre ; colour rose-red, or 
of yellow ; granular ; fracture irregular ; 
softer than glass ; sp. gr. 3.6B. It consists of 
Sulphuret of zinc, 82.92, Oxide of zinc, 15.34, 
Peroxide of iron, 1.84, Total 100-10. (Pog^ 
gendorjf, xxxi.) 
25. CARBONATE OF LEAD AND 
ZINC, comes from Mount Proxi, iri Sardinia 
in the form of small crystals, irregularly 
grouped together in rock quartz ; white and 
translucid ; hardness equal to calcareous 
B 
