Images
Formula: Hg
Native element, transition metal, may be monovalent Hg+1 or divalent Hg+2
Crystal System: Trigonal
Specific gravity: 13.596 measured
Hardness: Liquid
Streak: Liquid
Colour: Tin-white
Common impurities: Au,Ag
Abundance in the Earth's crust: 85 parts per billion by mass, 9 parts per billion by moles (CHC)
Abundance in the Solar System: 20 parts per billion by mass, 120 parts per trillion by moles (CHC)
HIGHLY TOXIC
Environments
Sedimentary environments
Hydrothermal environments
Hot springs
Native mercury is a secondary mineral resulting from
oxidation of cinnabar deposits. It is
solid below -38.9°C (Webmin). Although under ambient conditions mercury is liquid and so technically it does
not qualify as a
mineral, the IMA makes an exception and recognises it as one. It is usually found as small isolated drops associated with
cinnabar, but it can also be found as large liquid masses in
rock cavities; it is often found, along with cinnabar and other mercury
minerals, as a
precipitate from hot springs, in volcanic regions and in hydrothermal deposits formed at low temperature. Associated
minerals include
cinnabar, metacinnabar,
calomel, terlinguaite,
eglestonite, mercury-bearing
silver,
mercury-bearing gold, pyrite,
dolomite, baryte and
quartz
(HOM, Mindat).
Localities
At the Mariquita Mine (Sultana Mine), Usagre, Badajoz, Extremadura, Spain, native mercury is very common in
the fracture zones as thick droplets coating mercury chlorides and oxychlorides. Rarely, mercury is also
found in hollows in thick sheets of baryte and as inclusions in
baryte, associated with calomel;
mercury in these cases is of primary origin whereas
most of the mercury in the deposit is secondary
(MinRec 55.4.504).
The Rutland Cavern, Heights of Abraham, Matlock Bath, Derbyshire Dales District, Derbyshire, England, UK, is a show cave in
limestone. The specimen on which native mercury has been observed consists of a
5 x 3 x 1.5 cm piece of calcite matrix with included galena.
A cavity in the calcite containing
smithsonite was
observed to carry silvery globules of mercury measuring about 0.05 to 0.1 mm in diameter.
The cinnabar at Rutland Cavern is closely associated with
smithsonite formed from the alteration of
sphalerite,
and was probably a component of the sphalerite either in solid solution or as
inclusions. Being
more resistant to oxidation than the sphalerite, the
cinnabar remained intact during
sphalerite oxidation.
The sulphur in sphalerite is oxidised
at pH conditions
near 8 (mildly alkaline) at Eh values (see Pourbaix diagrams) above
about -0.2, leading to
the release of zinc ions, which in the carbonate rich environment forms
smithsonite at around the conditions required for forming native
mercury
(JRS 15.75-76).
Mercury from Rutland - Image
At the Hilderston Silver Mine, Linlithgow, West Lothian, Scotland, UK, micron-sized particles of mercury have been
reported, closely
associated with acanthite
(JRS 15.75-76).
At the Clear Creek claim, Goat Mountain, New Idria Mining District, San Benito county, California, USA, droplets and coatings of native
mercury fill cavities and veins throughout the mine, often in volumes exceeding 1 ml. Associated minerals include
cinnabar, edgarbaileyite,
eglestonite, montroydite,
mosesite, szymanskiite and
wattersite. Most native mercury has been found either filling isolated cavities in
quartz veins or associated with cinnabar as vein fillings.
The mercury shows strong affinity for quartz
(Minrec 36.4.347-348).
Mercury from Clear Creek - Image
At the Moon Anchor mine, Cripple Creek Mining District, Teller county, Colorado, USA, native mercury has been reported in small amounts
associated with cinnabar and coloradoite
(Minrec 36.2.174).
At the Huron River Uranium Prospect, Baraga County, Michigan, USA, native mercury is rare. A solitary, 0.1 mm, metallic drop of liquid
mercury was observed on a single specimen associated with mercury-bearing silver,
chalcopyrite, bornite and other sulphides
(R&M 87-2.134-139).
Mercury-bearing minerals include:
Alloys
leadamalgam
potarite
Sulphides
atheneite
cinnabar
donharrisite
hypercinnabar
imiterite
kenhsuite
metacinnabar
radtkeite
tennantite-(Hg)
Selenides
tiemannite
Tellurides
coloradoite
temagamite
Sulphosalts
aktashite
gruzdevite
hakite-(Hg)
laffittite
livingstonite
routhierite
vaughanite
vrbaite
Oxides
montroydite
Halides
arzakite
calomel
corderoite
eglestonite
hanawaltite
kadyrelite
kelyanite
kleinite
kuzminite
lavrentievite
mikecoxite
moschelite
mosesite
poyarkovite
terlinguaite
Carbonates
szymanskiite
Sulphates
gianellaite
Chromates
edoylerite
wattersite
Phosphates
artsmithite
Arsenates
chursinite
kuznetsovite
Sorosilicates
edgarbaileyite
Back to Minerals