mineral

Quartz (Chert/Chalcedony variant)

Silicon dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Tan, beige, translucent white to pale pink; Luster: Vitreous to waxy; Crystal structure: Hexagonal/Trigonal (though microcrystalline here); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Tan, beige, translucent white to pale pink
Luster: Vitreous to waxy

Identified June 16, 2026More mineral →

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Physical properties

Formation & geological history

Formed via precipitation of silica-rich fluids in sedimentary basins or hydrothermal veins. The coordinates (Southern France, Var region) indicate a location rich in limestone and sedimentary marls where silica nodules and quartz veins are very common geological features.

Uses & applications

Used in construction, glassmaking, electronics (piezoelectric properties), and as decorative pebbles or low-cost lapidary material.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Microcrystalline varieties like this one were historically used by prehistoric humans to make tools due to their sharp conchoidal edges.

Field identification & locations

Identify in the field by its inability to be scratched by steel, its waxy to vitreous luster, and lack of reaction to acid. Common throughout the Provence-Alpes-Cote d'Azur region in limestone outcrops.

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

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Metamorphic

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metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral