F, A. Genth—Contributions to Mineralogy. 319 
Ei i II. 
From Monfana. From Davidson Co., N. C. 
0. 0. 0. 
Ferric oxyd, OSG 2 a6 0°32) ae 
Plum ~ Ole Ae ss oe yeu ae 
Cupric  “ Be pate! 104 cee ee 
aR oxyd, 66°78 --6°85-- 68°78 - GBF Fee a7 
ed acid. 26°83 4°30 25°45 7°05 23°90 6°51 
Wat 5°94 3°47 2°80 
100-00 100°00 100°00 
The oxygen ratio between teroxyd of bismuth and telluric 
acid is very near equal to1:1. Some doubt remains, however, 
to the amount of water, and future investigations have to 
ascertain whether it contains one or two equivalents. The 
composition of the pure mineral would be either of the follow- 
ing: 
BiO;,TeO;+HO __ BiO;, TeO,;+2HO 
BiO, 234 70°69 BiO, 234 68°82 
TeO, 88 26°60 Teo; 88 25°88 
HO 9 2°71 2HO 18 5°30 
331 100-00 340 100-00 
3. Barnhardtite from Arizona.—I have observed ~ pe oo 
amongst the copper ores of Bill Williams Fork, Ariz o- 
ciated with metallic copper, ce ahd , copper, glance, aikony. 
tite 
rite, pyrites, chrysocolla, malac nd broc 
An analysis made by Mr. N. s. ign gave : 
Copper 50°41 p. ¢ 
Tron 20°44 
Sulphur 28°96 
99°81 
It showed a light admixture of copperglance ‘ 
4. Cosalite, anew mineral, 2PbS+ BiS,.—. A small specimen . 
i this fr interesting mineral was pen & me by Dr. 
with the eonalite was co cbaltine, as asc’ 
ascertain 
and cobalt-determination of gee ieee In aume 
