Images
Formula: Ca2(SiO4)
Nesosilicate (insular SiO4 groups), olivine group,
low-temperature,
orthorhombic paramorph of high-temperature, monoclinic
larnite
Crystal System: Orthorhombic
Specific gravity: 2.986 calculated
Hardness: 4½
Colour: Very light yellowish rose (caused by microinclusions of bernalite),
colourless in thin sections
Environments
Calcio-olivine may occur as the result of the conversion of larnite, which
is metastable below 520°C
(Mindat).
Localities
At the type locality, Xenolith no. 3, Lakargi Mountain, Upper Chegem volcanic caldera, Baksan Valley, Kabardino-Balkaria,
Russia, calcio-olivine occurs as rounded grains to 2-3 mm in size in
skarnated xenoliths from acid
ignimbrites. Associated minerals include
wadalite, thaumasite,
spurrite, rondorfite,
larnite, hillebrandite,
hematite, calcite,
brucite and afwillite
(Mindat).
Back to Minerals