Analcime and Apophyllite
Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
Mineral NameAnalcime and Apophyllite
Chemical FormulaAnalcime: Na(AlSi₂O₆)·H₂O; Apophyllite: KCa₄(Si₈O₂₀)(F,OH)·8H₂O
Mohs Hardness5
Lustervitreous
Streak Colorwhite
CleavageAnalcime: poor; Apophyllite: perfect on {001}
Fractureuneven to conchoidal
Specific Gravity2.3
Colorspink, orange, white, colorless, green
Transparencytransparent to translucent
Type LocalityBuco dell'Inferno (Lafreider Hölle), Siusi Alp (Seis Alp), Gardena Valley (Gröden Valley), Province of Bolzano-Bozen, Italy
Mineral GroupZeolites, Phyllosilicates
Usescollector's specimens
Associated Mineralsbasalt
Rarityuncommon
Description
A geode-like specimen featuring a cavity lined with pinkish-orange botryoidal analcime crystals and some clearer, blocky apophyllite crystals, all within a dark green volcanic matrix.
Geological Context
These minerals typically form as secondary minerals in vesicles and cavities of basaltic and other volcanic rocks, deposited from hydrothermal solutions.
