356 W. F. Hillebrand—Léillingite and other Minerals. 
however, be freed altogether from quartz and chalcopyrite. 
The specific gravity at 17° C. was 5-75. Making correction for 
443 per cent of quartz and 698 per cent of chalcopyrite of 
assumed specific gravities 2°65 and 42, this becomes 6:31. The 
analysis appears under I below. 
The more compact material, excluding as far as possible, the 
needles, gave, after deducting 59°75 per cent of gangue, the 
results under IT. 
III is the analysis of a mineral presented by Mr. William 
McCree as coming probably from the Missouri mine. In ap- 
pearance it differs in no respect from the compact material 
already described, except that no chalcopyrite is distinctly 
visible in the small specimens at my disposal and the quartz 
grains are less firmly cemented together. It contains, however, 
some lead which is entirely wanting in the other specimens 
analyzed, although the general formula is the same, hence I am 
led to believe that it came from some other portion of the 
workings or from an adjacent mine where ore like that from the — 
Missouri mine is reported to occur. The specific gravity was 
3°869 at 15° C., which becomes 6°680 on making correction for 
‘47-57 per cent of gangue of ascertained specific gravity, 2°64. 
be most marked blowpipe reactions for I, IT and III were 
entirely similar, a sublimate of sulphur appearing in the closed 
tube, sulphur dioxide escaping in the open tube and the fused 
fragment or powder on charcoal affording the bismuth reactions 
with great intensity. All were soluble in nitric and chlorhy- 
dric acids, in the latter with precipitation of silver chloride. 
; I I ul 
Bi 60-80 63°42 62°51 
A 0°89 4:09 9°89 
Cu 15-96 12°65 6°68 
74 
Fe 2°13 0-59 0°10. 
Zn 0°10 0-0 0°07 
S 19°94* 18°83" 17°90 
99°82 99°65 99°89 
After subtracting from I, 6-97 per cent; from H, 1°91 per 
cent, and from III, 0°83 per cent of chalcopyrite with the pro- 
sina of sphalerite represented by the zine, the atomic ravios 
ecome : | 
R : Bi, : Ss 
I 3°00 : 3°91 eet iy ts 
II 3°00 : 3°99 + - 14°98 
Ill 3°00 : 4°06 7 LBs 
* Calculated. 
