F, A. Genth’s Contributions to Mineralogy. 201 
an I i, Mean. Oxygen. 
oo. 329 not det. 3°29 contains 2-92 = 015 
: acid, 83115 31°75 3145 * 1633 = 09 
_ Alumina, 13-70 12°45 1oUG en a ee 
‘Chromic oxyd, 4°16 ~—_—not det. 416“ 198 t 739 = 04 
2 oxyd, 483 488° .“... 108 
ickel oxyd, 0-16 not det. 016 “* 0°08 
esia, not det, 42°10 4310 “ 17°93 $1840=01 
01 not det. OMT * 6: ORB 
Potash, not det. 0-06 006 3“ 001 | 
100°35 
Ith 
and are believed to be correct, I hesitate to express an opinion 
On this mineral. The composition corresponds nearly with the 
formula: sisXi+sR8i+H. Itis to be hoped that soon 
chrysolite is ser entine of a dark greenish grey color, resembling 
the duller viriciies of the vieatiae seleasibee of Wood’s mine, 
heaster county, Pa. I have no specimens showing the grad- 
val change from’ the chrysolite; it still shows however to some 
extent the granular structure of the same and here and there 
aoe of chromic iron are also intermixed withit. An 
* 
. 
: Oxygen. 
Ignition, - - - 955 contains 849 =15 
Chromic iron, cL. ey 
saree ee 
Nickel oxyd, * + * 0-27 a 0°06 
Ferrous oxyd, 3 3 1? : “« 159 1700 ox8 
Manganous Oxy’ d, -. > trace. 
Magnesia, - | . . 3862 “ 15-44 
Be ie en OOS 
Riliticacid, - - . 4367 4 22°78 =4 
The serpentine regions of Maryland, Pennsylvania, 
—SEconp Serres, Vor. XXXIM, No. 98.—Masce, 1862. 
