Genth. } 11s {Aug. 17, 
The analyses gave, after deducting in I. 4.96% of quartz, and in II. 
4.00% of quartz : 
IE NUE, Calculated. 
Au = 38.75 — 38.91 — 39.01 
Ag = 3.03 — 3.08 — 3.06 
Te = 57.32 — — 57.93 
V,O, — 0.05 —- 
FeO = 0.30 —— 
Al1,0,, MgO, &c., = 0.55 
not det’d. 
100.00 100.00 
These analyses give the ratios of (Au Ag): Te=1: 2; Au: Ag =7:1. 
The composition of calaverite, corresponding with the above analyses, 
is therefore : 
Au 3 Ag) Te,. 
In ‘‘ Nature,’ of March 8th, 1877, it is stated that at the February 
meeting of the Hungarian Geological Society, Professor Krenner an- 
nounced the discovery at Nagy-Ag, in Transylvania, of a pure Telluride 
of gold, in a crystalline state, which he calls ‘‘bunsenite’’ (a name al- 
ready given by Prof. J. D. Dana, in 1868, to the niccolous oxide from 
Johanngeorgenstadt, described by Bergemann), As I have no access to 
the original publication, I am unable to decide whether it is different from 
calaverite ; perhaps it is a variety even more free from silver than those 
of this country. 
5. TELLURITE. 
Already in 1842, Petz observed tellurous oxide, associated with native 
tellurium at Facebay and Zalathna in Transylvania. It has never been 
observed from any other locality, until I have lately noticed it with tellu- 
rium at the Keystone and Smuggler Mines, but especially in cavities and 
fissures of the native tellurium of the John Jay Mine, where it is found in 
minute white, yellowish-white and yellow crystals, mostly prismatic, often 
longitudinally striated, isolated or aggregated into bundles ; a few of the 
white crystals are acute rhombic pyramids. Cleavage eminent in one di- 
rection. 
Lustre vitreous inclining to resinous, on the cleavage plane adamantine. 
Readily soluble in ammonic hydrate ; the solution contains only tellurite 
of ammonium ; the composition of tellurite is therefore, as Petz had al- 
ready suggested, tellurous oxide = TeO,,. 
6. MAGNOLITE, A NEW MINERAL. 
This highly interesting mineral is the product of the oxydation of colo- 
radoite. It occurs very rarely with native mercury in the upper, decom- 
posed part of the Keystone Mine, associated with quartz, limonite and 
psilomelane. 
