Images
Formula: Mn2+3(PO4)2.4H2O
Hydrated normal phosphate, ludlamite group,
manganese-bearing mineral
Crystal System: Monoclinic
Specific gravity: 2.95 measured, 3.18 calculated
Hardness: 2½
Streak: White
Colour: Light golden brown, pale pink, white
Environments
Metaswitzerite occurs in granite pegmatites and in
zinc-bearing phosphorus
deposits. It forms by irreversible dehydration of switzerite on exposure to
air. Associated minerals include switzerite,
vivianite and scholzite
(Mindat, HOM).
Localities
At the Emmons pegmatite, Greenwood, Oxford county, Maine, USA, switzerite and
metaswitzerite occur rarely as patches
of crystals to 2 mm in rhodochrosite and altered
lithiophilite. The Emmons pegmatite is situated in a belt of
metasedimentary rocks
which originated as marine sediments which were subsequently deformed and metamorphosed. The Emmons pegmatite is an
example of a highly evolved
boron-lithium-cesium-tantalum
enriched pegmatite
(R&M 94.6.516).
At the type locality, the Foote Lithium Co. mine, Kings Mountain Mining District, Cleveland county, North Carolina, USA,
the local rocks are thin-layered amphibolite and
muscovite gneiss and
schist. The mine is a large open pit in a swarm of
granite pegmatites
of uniform composition containing roughly 32% quartz, 41%
feldspars, 20% spodumene, 6%
muscovite and l% other minerals. Numerous fractures and seams cut the
pegmatites; many contain
quartz and albite crystal druses. Other
minerals, including apatite, vivianite,
fairfieldite, pyrite,
rhodochrosite-siderite and
laumontite are present locally.
The mineralisation of the seams probably took place during the last stages of crystallisation of the
pegmatite. Metaswitzerite is found as masses and crystals
in some of the seams. It is usually associated, and sometimes intergrown, with
vivianite. Both metaswitzerite and
vivianite are abundant as very thin films coating fractures
(AM 52.1595-1602).
Back to Minerals