Silicates: Analcite

Composition: NaAlSi₂O₆.H₂O; potassium and calcium may replace sodium

Crystal system: Isometric; crystalline, massive and granular forms

5.2.1
analcite crystals

Properties:

• Vitreous lustre
• Colorless or white color
• White streak
• Knife barely scratches (Mohs Hardness 5)
• Below average density
• No cleavage
• Uneven fracture
• Not ferromagnetic
• Does not react with hydrochloric acid (HCl)

Occurrence:

Analcite occurs with other zeolites in veins and cavities in igneous rocks and also as a primary mineral in alkalic igneous rocks. Specialised characterisation is often required to distinguish the zeolite varieties.

5.2.2 analcite crystals	5.2.3 analcite crystals

Zeolites are important industrial minerals used mainly in the separation or purification of gases and liquids.

5.2.4
analcite crystals