Reéxamination of American Minerals. 377 

Sili 3 g Y . : i 22°05 
Peroxyd of i iron, : ! % nx 8 .. 1766 
: : : : 1640 | 
Protea of i iron, ; : : : : . 30°78 
ggg Z - . , : ‘ 0°89 
a, : 
Potash, bi O14 
Water, 1144 
99°36 
The peroxyd of iron is a little higher, and the protoxyd a lit- 
tle lower than in the analysis of Owenite, but this arose from th 
partial decomposition of the specimen. The correct analysis of 
Thuringite is that first given, and the formula deduced by Mr. 
Genth from it is to be looked upon as the correct one, namely— 
2k* Si+ #e Si+ 6H, 
' corresponding to the oxygen ratio for 
Ry, B 5i, H,. 1:18:15: 1. 
In looking over some minerals placed in my hands by Mr. 
Markoe, I have found a specimen of Thuringite coming from the 
Hot Springs of Arkansas. Its identity is made out without the 
slightest difficulty, as all its physical characters correspond most 
ty with the Thuringite, its sp. gr. being 3:184 and composi- 
” Silica : ‘ ; ; - . 23°70 
Paoxya of iron, ; : ; ; i <3 tele 
Alu ; é 3 . . A 1654 
oe of i iron, : ; i : . - 8814 
Magnesia, ; ‘ : . 1°85 
oe 1-16 
Soda, : 
ee t 0°32 
Water, ‘ s “ ; : Z - 1090 
99°74 
An interesting fact connected with this mineral as shown by 
this investigation is, that although not crystalline, or at least very 
obscurely so, yet coming as it does from three localities so widely 
Separated as ‘Thuringia, the Potomac, and Arkansas, it is never- 
theless ne a unmixed with any other mineral, as the anal- 
yses indica 
41. Xenotime of Georgia. 
In examining a few years ago some’ of the residue of gold 
rhein from Clarksville, ie be in eer assreente of Prof. 
oe saa oe no. goninhe: 
ter at hand, they were sent to Mr. Teschemacher, who referred 
them, after a partial examination, to erie Prof. Gibbes sub- 
sequently examined their form, and pronounced them Xenotime, 
(Am. Jour. Science, 2nd Ser., xiii, 143). "Blass then, from ma- 
Srconp Serres, Vol. XVIII, No. ay 1854. 48 
