312 F. A. Genth—Contributions to Mineralogy. 
altaite, III, and with the melonite (see below), did not contain 
any, and the material for analysis when dissolved in nitric acid, 
did not separate any brown polis it contained, therefore, the 
true hessite. 
Altaite—This very rare mineral also occurs at the Sta 
islaus mine as already observed by Charles A. Stetefeldt, on 
it appears to be the mineral to which W. P. Blake refers in 
his catalogue. I noticed it in eter quantities with the 
petzite from the Golden Rule min 
Itis easily distinguished from the other tellurids by its tin- 
white color, which has a slight but distinct greenish yellow hue. 
Tarnishes with a bronze yellow color. Cleavage distinctly, in 
some pieces eminently cubical. angen brilliant metallic 
luster. Hardness below 3. Streak gray. 
Analysis I was made with an almost pure piece; after de- 
ducting 1°03 p. c. . of quartz, and 1°96 p.c. for IT, which was less 
pure, T obtaine 
I Requires Te. IL. Requires Te. 
Lead 60°71 87°54 47°84 29°58 
ee be oF 0°69 11°30 6°70 
Ea a as 0°26 0°08 3°8 1°25 
Tellurium,.___- 87°31 37-00* 
; 99°45 38°31 100-00 37°53 
These oped would represent the composition of the two 
specimens a 
ae 99°25 77°42 
Hessite, 2°20 
two last analyses were eo Ta pe some from it Spree 
ae iggins. It gave results which were, 
eral points of view, of interest. After, from the est that 
could be found, the carbonates had been removed by dilute chlor- 
hydric acid and it had been completely washed, it was pulver- 
ized and the liehter portion washed off. The heavier portion gave 
after deducting 8:00 p. c. of free gold and 3°45 p.c. of quartz: 
(Mixture of re and hessite) IIT. 
4°49 
Pe. 
es 
ay: 
=F 
Z 
*E 
3e 
5? 
Silver, requiring Te 26°36 
oo og ae eamiaa sae ite 10°89 
Jellamam, . ........ 37°14* 
ee 37 87°25 
e contains, therefore, 70°85 p.c. of true hessite and 
This result was quite surprising, since the material appeared 
ee ir pa ye ened to contain a far 
percentage of altaite. 
