OCCURRENCE OF A NEW MINERAL AT BROKEN HILL. 369 
Argentite—Silver Sulphide (Ag,S).—Very rare, only small 
specimens met with, contained generally in dyscrasite, sometimes 
in small crystalline masses, showing a well marked cubical struc- 
ture ; rarely in cubes possessing the peculiar shrivelled appearance 
reported by Cox and Ratte (Mines and Minerals). The purest 
specimens were never tested; a typical piece gave seventy-eight 
per cent. silver, the impurity being probably lead sulphide. 
Very soft, sectile, but not perfectly so. Depth about one hundred 
and twenty feet (vertical); lode-gangue principally limonite. 
Stephanite—Antimonial Silver glance (Ag,;SbS,).—Found in 
one part of the mine only in small quantity, in soft puggy ground 
between two veins of mixed calcite and siderite. Specimens 
detached and small, all crystallised. Rhombic six sided prisms 
and tables; macles frequent. Specific gravity 6°23. Contains 
67:1 per cent. silver; no silver compounds associated. Depth 
between three hundred and eighty and four hundred feet (vertical); 
lode-gangue calcite and siderite. 
Pyrargyrite—Ruby silver ore, (Ag;SbS,). Also found in small 
quantity only; very rarely crystallised in hexagonal prisms. Small 
amorphous pieces apparently very pure, translucent on edges, gave 
56:3 per cent. silver. Mostly in films in cleavages of siderite, 
rarely dendritic in calcite, the latter very dark in colour, rather 
sectile with the characteristic streak. Always with or near 
tetrahedrite, rarely with pyrite and pyrrhotite. Various depths; 
lode-gangue siderite and calcite. 
Sternbergite—Sulphides of silver and iron (AgFe,S,).—Very 
rare, found encrusting a piece of dyscrasite weighing over fifty 
pounds, at a depth of one hundred and fifty feet. Several lumps 
(detached slugs) of dyscrasite were found in close proximity, but. 
only with one was this rare ore associated. Amorphous and more 
or less impure through admixture with pyrargyrite. The purest. 
piece tested gave silver 33°94 per cent., iron 30°76 per cent., and. 
contained a little antimony, quantity not determined. Fused 
B.B. to metallic globule; marked paper slightly ; streak black ;. 
X—Nov. 1, 1893.] 
