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Formula: Pb8As10Sb6S32
Sulphosalt, sartorite group,
arsenic- and antimony-
bearing mineral
Crystal System: Monoclinic
Specific gravity: 5.26 calculated for the ideal formula
Hardness: 4
Streak: Black
Colour: Grey
Luminescence: Not fluorescent
Environments
Metamorphic environments
Hydrothermal environments
Localities
At the type locality, the Uchucchacua Mine, Oyón District, Oyón Province, Lima, Peru, the deposit is a
silver – manganese –
lead – zinc vein, replacement and
skarn mineral deposit hosted in
limestone. The deposit is surrounded by
andesitic and dacitic
volcanic deposits and intrusions of Late Oligocene age (approximately 25 million years ago). Ores were generated as
fissure infill and replacement of adjacent limestone.
In Stage 1, silicates of manganese,
iron and calcium (such as rhodonite
and bustamite) were deposited.
In Stage 2, friedelite,
magnetite and an array of common sulphides were deposited, including
iron-rich sphalerite,
manganese-rich wurtzite and
alabandite, with unstable
pyrrhotite. Main gangue minerals
were calcite, kutnohorite,
rhodochrosite and quartz.
In the late Stage 3, silver, arsenic,
and antimony were introduced, forming sulphosalts. In this stage,
iron-poor sphalerite and
alabandite coexist with calcite
and pyrite. Some authors ascribe
orpiment, marcasite and
siderite to a
supergene stage, together with
manganese oxides, goethite and
cerussite.
This deposit was a source of benavidesite and
uchucchacuaite, and the Socorro section, which was rich in
alabandite and in which the samples with hyršlite were found, was
the source of menchettiite,
manganoquadratite,
keutschite, agmantinite and
spryite.
Hyršlite was found in a sample in which menchettiite was
described in association with orpiment. Subsequently, it was found in two
additional samples which contain orpiment and
lead – silver –
manganese – antimony –
arsenic – sulphur sulphosalts. The
hyršlite occurs in close association with orpiment,
quartz,
tennantite-tetrahedrite,
menchettiite and
manganoquadratite in a
calcite matrix. Hyršlite occurs as very rare individual crystals,
closely associated with orpiment,
manganoquadratite,
stibnite and lead –
silver – manganese –
antimony – arsenic –
sulphur sulphosalts, and as euhedral to anhedral grains intergrown with
manganoquadratite and lead –
silver – manganese –
antimony – arsenic –
sulphur sulphosalts, including
menchettiite. The maximum crystal size of hyršlite is about
300 microns
(EJM 30.6.1155-1162).
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