A natural association of apophyllite, stilbite, and red heulandite from the basalt of the Deccan Traps, Maharashtra, India. Each mineral here tells you it belongs to this place: the stilbite in soft sheaf-like or bowtie clusters, the tabular heulandite warmed to red-orange by natural iron, and the apophyllite in bright, blocky crystals. Apophyllite is not a zeolite itself, but it almost always forms alongside them in the same volcanic cavities, which is why the three so often appear together on one piece.
Mineral: Apophyllite (KCa₄(Si₈O₂₀)(F,OH)·8H₂O), stilbite and heulandite (zeolite group aluminosilicates)
Crystal system: Apophyllite tetragonal; stilbite and heulandite monoclinic
Origin: Deccan Traps, Maharashtra, India
Hardness: 4.5 to 5 for apophyllite, 3 to 4 for the zeolites; a soft, delicate specimen, handle by the base
Treatment: None
Dimensions: 6 × 4.3 × 4.3 cm
Weight: 124 g
You'll receive the exact piece photographed.