metamorphic

Blue Schist / Lydian Stone / Chert with Glaucophane

Metamorphic rock containing quartz and glaucophane

AI-generated identification · may be incorrect

Hardness of 6-7 on the Mohs scale, color ranges from greyish-white to distinctive blue veins, dull to vitreous luster, cryptocrystalline structure, conchoidal fracture.

Identified July 28, 2026More metamorphic →

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Physical properties

Hardness of 6-7 on the Mohs scale, color ranges from greyish-white to distinctive blue veins, dull to vitreous luster, cryptocrystalline structure, conchoidal fracture.

Formation & geological history

Formed through regional metamorphism of clay-rich sediments or basaltic rocks under high-pressure and relatively low-temperature conditions, typically in subduction zones.

Uses & applications

Used primarily as a geological specimen for collectors, decorative landscaping stones, and sometimes polished into ornamental cabochons.

Geological facts

Blue coloration in such stones often indicates the presence of sodium-rich amphibole minerals like glaucophane, which form deep within the Earth's crust under immense tectonic pressure.

Field identification & locations

Can be identified in the field by its distinct blue swirled banding or veining against a lighter matrix, hardness that scratches glass, and smooth water-worn texture if found in riverbeds or beaches.