ANALCIME
Analcime is one of the feldspathoid minerals. It
is a hydrous sodium aluminosilicate (NaAlSi2O6·H2O).
It tends to form trapezohedral
crystals (24-sided crystals consisting of double square pyramid crystals with each
of the 8 faces having 3 trapezoid faces). It has a dull to glassy,
nonmetallic luster, variable color, white streak, no cleavage, and a moderate
hardness (H = 5 to 5.5). Analcime occurs as an igneous mineral or a hydrothermal
mineral that fills vesicles in some igneous rocks.
Analcime
phenocryst (crystal is 9.5 mm across) in blairmorite from Blairmore, Alberta,
Canada.