In the same district as the type locality, the Kurunegala District,
graphite has been mined since 1872, and is one of only
two major mines in Sri Lanka. The mine changed hands several times,
and it is now operated by Kahatagaha Graphite Lanka Limited (KGLL), that is fully government owned; there have,
however, been accusations of mis-management and corruption.
The mine is at an altitude of only 25 m (according to KGLL) but the workings go down 610 m.
Images
Formula: BaFe
Phyllosilicate (sheet silicate), brittle mica group,
barium-bearing mineral
Crystal System: Monoclinic
Specific gravity: 3.91 to 3.94 , measured 3.91 calculated
Hardness: 3 to 4
Streak: Grey-white
Colour: Black
Luminescence: Not fluorescent under UV
Environments
Localities
At the type locality, the Wilagedera iron prospect, Kurunegala District, North Western Province, Sri Lanka,
anandite occurs as thin bands and lenses within a magnetite -
baryte - sulfide ore zone. The enclosing
calc-schists and
calc-gneisses of Precambrian age (from 4.6 billion years ago, when
the Earth began to form, to 541 million years ago) have been subjected to
granulite grade metamorphism
(AM 70.1298-1308).
Associated minerals include magnetite,
chalcopyrite, pyrite,
pyrrhotite and baryte
(HOM).
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