Analcime... On aurait le choix ?
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L'analcime cristallise dans six des sept systèmes cristallins : cubique, tétraédrique, trigonal (syn. hexagonal), orthorhombique, monoclinique, triclinique.
Analcime with aegirine and natrolite from Mont Saint-Hilaire, Québec (size: 78 x 65 x 53 mm)
General Category Zeolite Formula (repeating unit) NaAlSi2O6·H2O Strunz classification 09.GB.05 Identification Color White, colorless, gray, pink, greenish, yellowish Crystal habit Typically in crystals, usually trapezohedrons, also massive to granular. Crystal system Cubic; tetragonal, orthorhombic, or monoclinic, pseudocubic, with degree of ordering.