408 
DESCRIPTIVE MINERALOGY. 
This mineral resembles some dark varieties of pyroxene, from which it was first distin¬ 
guished by Mr. Levy. Mr. Children found it to contain silica, iron, manganese, lime, and a 
minute cpiantity of titanium. 
LOCALITY. 
St. Lawrence County. The only known locality of babingtonite in the United States, is 
at Gouverneur in this county, where it was first noticed by Prof. Shepard, coating crystals of 
feldspar. 
ORDER III. ZINC. 
This order contains only a single species, viz : 
1. Zinc Blende; and to this maybe added the artificial oxide known by the name of 
Cadmia. 
ZINC BLENDE. 
[From the German, signifying glistening ; in allusion to its lustre.] 
Zinc Sulfure. Hauy .— Sulphuret of Zinc. Cleaveland and Phillips. — Blende, or Sulphuret of Zinc. Thom¬ 
son. — Dodecahedral Zinc-Blende. Jameson. — Dodecaedrische Granat-Blende. Mohs. — Blende. Beudant 
and Shepard. 
( Thomson). 
in nitric acid 
Description. Colour brown, yellow, grey, green, red and black. 
Streak varying with the colour. It occurs regularly crystallized ; also 
massive and disseminated. Primary form the rhombic dodecahedron, 
Fig. 483. Its secondary forms are very numerous. Cleavage perfect, 
parallel with the primary faces. Fracture conchoidal. Brittle. Lus¬ 
tre splendent, sometimes adamantine. Varies from transparent to 
opaque. Hardness from 3.5 to 4.0. Specific gravity from 4.00 to 
4.20. Before the blowpipe, it usually decrepitates ; and though gene¬ 
rally infusible even with borax, it sometimes melts into a scoria 
Its powder in sulphuric acid gives out sulphuretted hydrogen. Difficultly soluble 
; its solution giving a white precipitate with ammonia, which is soluble in an 
excess of the alkali. 
Zinc blende may be distinguished from those varieties of galena, garnet and oxide of tin, 
which it sometimes resembles, by the ease with which it yields to cleavage in the direction of 
the primary faces. 
