370 J. G. H. Godfrey—Associution of Stibnite and Cinnabar. 
Its colour is bright lead-grey and its streak red, not black as with 
stibnite. According to an analysis by Barcena, its composition has 
been found nearly to correspond to the formula 4 Sb S*+4+ HgS + 
Perst ' 
In Nevada and New Zealand, stibnite and cinnabar are said to be 
found associated with each other, but the author is not aware of any 
publications about this association. 
A few years ago cinnabar in considerable quantity was dis- 
covered in the refuse heaps of the Meria antimony mines? situated 
in the commune of Ersa, Cape Corse, in the island of Corsica.’ 
Lodes, containing the antimony chiefly as sulphide rarely as oxide, 
occur there in serpentine, talcose schists, or metamorphic limestone. 
They usually run from nearly N.W. to 8.E., vary in width from a few 
inches to 11 ft., and are composed of stibnite (stibiconite), cimnabar 
in greatly varying quantities, iron pyrites and as gangue, fragments 
of the containing rock, clay resulting from the decomposition of the 
same, quartz, calcite and but rarely gypsum. Experience has shown 
that when calcite becomes predominant as gangue, no cinnabar is 
found associated with the stibnite. In the Castello lode stibnite in 
fine needles occurs dispersed throughout the calcite, which forms” 
there the main constituent of the lode. The calcite, which retains 
its crystalline form, is more or less darkened according to the 
quantity of inclosed needles of stibnite. It frequently occurs, that 
in some large rhombohedral masses of calcite some of the corners 
are rendered dark by the presence of stibnite, whereas the remainder 
retains its original white colour. 
Cinnabar, always in the amorphous state, occurs in these lodes; 
either filling up the interstices left between the crystals of stib- 
nite (Seraggio lode), or intimately mixed with amorphous stibnite, 
and also in the shape of thin (up to half an inch thick) ribs 
inclosed in amorphous stibnite (Vallone and Fossato lodes). 
The presence of intimately intermixed cimnabar in amorphous 
stibnite is always indicated by irridescence of the latter, and this 
property is made use of in separating ores containing cinnabar from 
those which are composed of amorphous stibnite only. ‘The 
Vallone and Fossato lodes yield at present mixed antimony and 
cinnabar ores in considerable quantities. 
The observed facts appear to prove that in these lodes the deposi- 
tion of cinnabar has taken place subsequent to that of stibnite, and 
most likely also subsequent to that of calcite, which appears to form 
the chief mineral of the Castello lode. 
In Tuscany, near Selvena, situated close to Santa Fiora, an associa- 
tion of stibnite and cinnabar has also been observed. Cinnabar 
occurs there, usually in small crystals, seldom in small lumps, in 
clay-seams interstratified with Nummulitic limestone. The layer of 
limestone at their junction has been found impregnated with fine 
1 First discovered at the Spellonche lode, where the ore picked from the refuse is 
said to have contained 28 per cent. of mercury. 
* See also: Hollande, Géologie de la Corse, Ann. des Sciences géologiques, 1877, 
p- 105. 
