Larnite

Formula:  Ca₂SiO₄

Origin of name:  Locality; Larne, County Antrim, Northern Ireland

Crystal system:  Monoclinic

Crystal class:  2/m

Twinning: 

Unit cell: a = 5.48, b = 6.76, c = 9.28, β = 94.55°

Colour:  Colourless to gray

Diaphaneity:  Transparent to translucent

Luster:  Vitreous

Habit:  Crystals tabular, imperfect; massive, granular

Hardness:  ~ 6

Specific gravity:  3.28

Cleavage:  1; {100} distinct

Tenacity: 

Streak: White

Synonyms/varieties:

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