Images
Formula: (Ca,Sr)(Mg,Fe2+)2Al(PO4)3
Phosphate, strontium-bearing mineral
Crystal System: Orthorhombic
Specific gravity: 3.162 calculated
Colour: Slightly pale pinkish brown, colourless
Environments
Lasnierite is a relatively new mineral, approved in 2018 and to date (May 2023) reported only from the type
locality.
Localities
The type locality is the Lasnierite type locality, Sahatsiho Ambohimanjaka, Ambositra, Amoron'i Mania, Madagascar.
Lasnierite was discovered as inclusions in a 1.97 carat faceted
lazulite-bearing quartz from Mount
Ibity, obtained on the market, and its exact provenance is unknown. The cut stone originated from the
lazulite-bearing
metaquartzite horizon of sedimentary origin. The metamorphic
sequence reached greenschist to
amphibolite facies grade, at 450 to
550oC and 3.5 kbar. In addition to quartz and
lazulite, the mineral association contains
chlorapatite, celestine,
monazite-(Ce),
xenotime-(Y), augelite,
trolleite, svanbergite,
goyazite, crandallite,
berlinite, anhydrite,
ilmenite, titaniferous
magnetite,
rutile, hematite,
muscovite, kyanite,
zircon, dumortierite,
tourmaline, clinoamphibole
and undetermined tin-bearing acicular inclusions.
The lasnierite forms transparent slightly pale pinkish brown euhedral crystals 60 to 120 µm in length on the
gem surface.
(EJM 31.2.379-388).
Back to Minerals