mineral

Quartz Geode Fragment with Iron Staining

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Clear to white with reddish-brown iron oxide; Luster: Vitreous to greasy; Crystal Structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture.

Hardness: 7 (Mohs scale)
Color: Clear to white with reddish-brown iron oxide
Luster: Vitreous to greasy

Identified June 2, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 (Mohs scale); Color: Clear to white with reddish-brown iron oxide; Luster: Vitreous to greasy; Crystal Structure: Hexagonal/Trigonal; Cleavage: None/Conchoidal fracture.

Formation & geological history

Formed through hydrothermal processes or gas bubbles in volcanic rock where silica-rich fluids precipitated over time. The iron staining occurs from groundwater infiltration containing hematite or goethite.

Uses & applications

Primarily used for mineral collecting, lapidary work (tumbling), and as decorative ornaments. High-purity quartz is used in electronics and glass manufacturing.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Iron-stained quartz is often called 'Ferruginous Quartz' or 'Hematoid Quartz' when the red color is integrated.

Field identification & locations

Identify by its hardness (scratches glass), hexagonal crystal habits, and lack of cleavage. Common in many geological environments worldwide, especially in desert or mountainous regions.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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

Metamorphic Rock

Biotite Schist

Biotite-rich Schist [K(Mg,Fe)3AlSi3O10(F,OH)2]

metamorphic