Dr. Genth’s Contributions to Mineralogy. 169 
corresponding with the formula 2(3RO,8:03)+(3R2 a $103) 
+6HO. 
Owenite is closely allied to some other minerals, viz., Aphro- 
siderite and Thuringite, and they all resemble each other so very 
much that their difference can be detected only by a chemical 
examination. Aphrosiderite is a mineral not generally known; 
found at several localities in Nassau, and distinguished from 
earthy chlorite by Fridolin Sandberger, who gave an analysis of 
it in his ‘‘ Uebersicht der geologischen Verhaltnisse des Herzog- 
thums Nassau,’ but without calculating its formula. He found 
that it contains : 
SiO; oi 26 “45 which contains oxygen - "3 
Als O$ mee 2S 93 
eO = 44-94 “ oe - 
MeO eS Ft “ OAl t 19 23 
100°74 
The ratio of oxygen of RO: Als O23: SiQs : HO is 
10:23: : ae ED Be wes or very near 
ge ppl a sate aa ae formula aa) SiOs y+-(3Al2 Os; 
iO 
eds S ; thuringite according to an analysis of Rammels- 
berg, is 3(3RO, Si Os)+(2Fes Os,8103)+-9H0. 
The relation of these three minerals will be seen from the 
following formule : 
Owenite = 2(3RO, $i Os)+(3R20s, SiO:)+6HO; 
rena Adtay = 3(3RO,8i0:)+(3Al20:, 8103)+6HO; 
Thur = 3(3RO,Si03)+(2Fe: : Os, SiOx) +9HO. 
a itis miner is named in honor of Dr. David Dale Owen, U.S. 
eolog 
- dimmererite—Emerald Nickel —A year ago, before I had 
received my foreign journals, I published two analyses of Kam- 
Mmererite, and finding these different from Kammererite and Rho- 
dochrome, I proposed for it the name “ Rhodophyltlite.” On be- 
ing informed that Dr. J..L. Smith was about making an investi- 
gation of the same mineral, I wrote him that the conclusion to 
which I had arrived, after comparing the results of my analyses 
and those of Mr. Hermann, was, that Kimmererite and my Rho- 
dophyllite were the same mineral, and requested him to mention 
it in bie a ee This ought to have been sufficient. Notwith- 
Siete Serres, Vol. XVI, No. 47 wep ae —— 
