50 
NATURAL HISTORY. 
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Case 8 contains a suite of specimens of sulphuret of lead or galena, 
which include a great variety of modifications of crystals, detached and 
grouped together, (the more remarkable modifications, besides those of 
Great Britain, from the Hartz and from Saxony,) in combination with 
blende, pyrites, and many other substances; galena of various grain, 
massive and disseminated; galena of corroded appearance, decomposed 
and regenerated; the compact and specular variety, called slickenside 
by the Derbyshire miners, &c _ steinmannite, probably a distinct anti- 
monial sulphur salt, is placed here, because several compact varieties of 
sulphuret of lead appear to be a mixture of it and common galena. 
Case 9. Sulphuret of bismuth, or bismuth-glance, in acicular crystals, 
from Riddarh}dtan, &c. — Sulphuret of copper and bismuth, called 
copper-bismuth, from Wittichen, in the Black Forest.—The needh-ore 
of Weraer, a triple sulphuret of bismuth, lead, and copper, only found 
neai* Ekatherineburg, in Siberia, accompanied by native gold, &c. 
_ Sulphuret of copper and tin, or tin-pyrites, only found in Cornwall: 
it is called bell metal ore on account of its colour, which is frequently 
that of bronze. The remainder of this case is taken up by a con¬ 
siderable suite of specimens of sulphuret of mercury or cinnabar, (chiefly 
from Almaden, in Spain, and from the Palatinate,) divided by Werner 
into the dark-red (by far the most common variety), and the bright-red 
cinnabar (native vermilion, much esteemed by painters); the idrialine- 
cinnabar, or brand-ei’Z, a mixture of cinnabar with the bituminous sub¬ 
stance called idrialine, and earthy particles, from Idria, in Carniola, 
compact and slaty : the same with globulai* bodies composed of con¬ 
centric testaceous laminffi, being the korallenerz (coral ore) of Werner. 
Case 10. Sulphuret of silver, common silver glance, or henhelite, 
massive, ciystallized, and in other external forms, among which are the 
laminar and capillary: the black silver, which is often seen coaring 
other ores of silver, appears to be a pulvemlent variety of this species; 
_ ^flexible silver glance, or sternbergite; — the scarce donacargyrite, or 
schilfertz of German mineralogists, which, however, is considered as a 
combination of several sulph-antimoniurets of silver and lead. — Sulphu¬ 
ret of antimony, or grey antimony, compact, foliated, radiated, and 
plumose : the more remarkable among these are the specimens of crp- 
tallized antimony in splendid groups, especially from Transylvania; 
radiated o-rey antimony with baroselenite, realgar, kc.; plumose anti¬ 
mony (feather ore), some vaideties of which,* appearing like delicate 
wool or down, display a fine iridescent blue, yellow, and red tarnish*.— 
With these is placed the hartmannite, a doubtful species, said to be a 
sulphuret of antimony and nickel. 
Case 11. Pait of this Case is occupied by the specimens of sid- 
phuret of arsenic, viz. the yelloiv orpiment, massive and in striated, 
transpai'ent, separable laminae; and the red orpiment or realgar, 
perfectly massive and crystallized, but decomposing by the action of 
light into an orange-coloured powder. 
The rest of this and part of the next Case contain the simple and 
double sulphur-salts formed by the sulphurets of antimony or arsenic, 
with basic sulphurets of electro-positive metals; among these may be 
* Several of the plumose varieties of grey antimony are referable to the sulphur- 
salts in the next glass case. 
