Meionite
Meionite | |
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Meionite (scapolite) crystals (cross-shaped) in a quartz matrix, 7.2 x 4.0 x 3.0 cm. Worcester County, Massachusetts. | |
General | |
Category | Tectosilicate < br/>Scapolite group |
Formula (repeating unit) | Ca4Al6Si6O24CO3 |
Strunz classification | 09.FB.15 |
Crystal symmetry | Tetragonal 4/m - Dipyramidal |
Unit cell | a = 12.179(1)Å, c = 7.571(1)Å |
Identification | |
Color | Colorless, white, grey, pink, violet, blue, yellow, orange-brown, brown |
Crystal system | Tetragonal |
Cleavage | Distinct/good on {100}{110} |
Fracture | Irregular/uneven, conchoidal |
Tenacity | Brittle |
Mohs scale hardness | 5 - 6 |
Luster | Vitreous, resinous, pearly |
Streak | White |
Diaphaneity | Transparent, opaque |
Specific gravity | 2.74 - 2.78 |
References | [1][2][3] |
Meionite is a tectosilicate belonging to the scapolite group with the formula Ca4Al6Si6O24CO3. Some samples may also contain a sulfate group. It was first discovered in 1801 on Mt Somma, Vesuvius, Italy.
References
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