mineral

Stilbite

Stilbite-Ca (Hydrated calcium sodium aluminum silicate), NaCa4(Si27Al9)O72·28H2O

AI-generated identification · may be incorrect

Hardness: 3.5-4 (Mohs); Color: Peach, salmon pink, or white; Luster: Pearly to vitreous; Crystal structure: Monoclinic; Cleavage: Perfect in one direction; Specific gravity: 2.1 to 2.2.

Hardness: 3
Color: Peach, salmon pink, or white
Luster: Pearly to vitreous

Identified February 14, 2026More mineral →

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Physical properties

Hardness: 3.5-4 (Mohs); Color: Peach, salmon pink, or white; Luster: Pearly to vitreous; Crystal structure: Monoclinic; Cleavage: Perfect in one direction; Specific gravity: 2.1 to 2.2.

Formation & geological history

Formed through hydrothermal activity in the cavities (vesicles) of basalt and other volcanic rocks. It belongs to the Zeolite group and typically forms during the late-stage cooling of volcanic flows where mineral-rich water circulates.

Uses & applications

Primarily used as a collector specimen and for metaphysical purposes. Industrially, zeolites like stilbite are used as molecular sieves for water purification and gas separation due to their porous nature.

Geological facts

Stilbite's name comes from the Greek word 'stilbein,' meaning 'to shine,' referring to its pearly luster. It is often found in unique 'bow-tie' or wheat-sheaf crystal habits, which are highly prized by mineralogists.

Field identification & locations

Identify in the field by its distinct salmon-pink color, pearly luster on cleavage surfaces, and its typical association with other zeolites like apophyllite in volcanic matrix. Common locations include the Deccan Traps in India, Iceland, and New Jersey, USA.