mineral

Quartz (Chalcedony/Agate nodule)

Silicon dioxide (SiO2)

Hardness: 7 on the Mohs scale. Color: Translucent greyish-white with brownish matrix areas. Luster: Vitreous to waxy. Crystal structure: Trigonal (microcrystalline/cryptocrystalline variety). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Translucent greyish-white with brownish matrix areas
Luster: Vitreous to waxy

Identified August 6, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the deposition of silica-rich groundwater within cavities of host rocks (often volcanic or sedimentary) at low temperatures, occurring over millions of years.

Uses & applications

Used in lapidary arts, jewelry, decorative items, and as mineral specimens for collectors.

Geological facts

Quartz is one of the most abundant minerals in Earth's continental crust. Chalcedony forms the basis for many precious gemstones including agate, jasper, and onyx.

Field identification & locations

Can be identified in the field by its high hardness (scratches glass), waxy luster, and conchoidal fracture. Often found in riverbeds, gravel deposits, and weathered out from volcanic host rocks.

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Soil with Mineral Detritus and Quartz Fragments

Regolith / Silicate Mineral Aggregate

sedimentary

Limonite / Goethite (Iron Ore Mineral nodule)

FeO(OH)·nH2O / FeO(OH)

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Septarian Pebble

Septarian nodule / Concretion

sedimentary

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

mineral

Schist

Metamorphic