248 Mineralogical Notices. 
p tacked also by chlorohydric acid, and when pulverized by a boil- 
ing lye of caustic potash. Composition :— 
iS) Sb Ag Fe Zn , 
~ 1. 19°88 2995 25:03 2474 054 0:30 0-40 = 100°34 
me. Ss 19°21 2960 2446 25:05 O61 0:26 032 99°51 
es 3 19°14 2975 2481 2494 O70 0:22 O387T= 99-93 
ere r F 
. The result gives the formula PbS+Ag S+Sb S? [equivalent 
- to2(Pb, Ag)S+Sb S°*,] = Sulphur 19-08, antimony 30-66, silver 
25-65, lead 24:61= 100. 
~ 4. M. Damour observes that the composition approaches most 
4 nearly that of the Schilfglaserz (Freislebenite ), the mean of two 
analyses of which by Wohler, is, S 18:74, Sb 27-38, Ag 22°93, 
~ Pb 30-27= 99°32. 
| The. formula is identical in general character with that of 
‘4 feather’¢ Be eigromorpiute of Rammelsberg), it differing only 
. < having half the lead replaced: by silver. Wohler’s formula for the 
. .. Freislebenite corresponds to 7(Pb, Ag) S+3Sb S°* or 24(Pb, Ag)S 
- © 4.$b $3, the silver and lead being in the proportions of 3 to 4.*] 
oe HS Il. Descrisep Species. 
nite from the Muschelkalk near Saarbriicken, (R. Wil- 
, J. fir prakt. Chem., xlix, 154, 1850.)—This ead : 
m Michatein 
. 4 «. erystalline granular, and yellowish gray in color. G=e 
2 =™. % “ a : ar: ‘ 
» ..* Composition according to Wildenstein :— 
4 64630 Oa 3050 Mg2013 Fe117 Ktrace, Clay and sand 1:88 = 99°98 
a a 
_? 
: a 
EAS 
