mineral
Iron-stained Quartz / Chalcedony Pebble
Silicon Dioxide (SiO2) with Iron Oxide inclusions
AI-generated identification · may be incorrectHardness: 7 on Mohs scale. Color: Translucent yellowish-orange, honey-brown to reddish, caused by iron oxides. Luster: Waxy to vitreous. Crystal Structure: Microcrystalline or trigonal quartz. Cleavage: None (conchoidal fracture). Specific Gravity: 2.6-2.65.
- Hardness
- 7 on Mohs scale
- Luster
- Waxy to vitreous
Identified More mineral →
Explore Iron-stained Quartz / Chalcedony Pebble in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on Mohs scale. Color: Translucent yellowish-orange, honey-brown to reddish, caused by iron oxides. Luster: Waxy to vitreous. Crystal Structure: Microcrystalline or trigonal quartz. Cleavage: None (conchoidal fracture). Specific Gravity: 2.6-2.65.
Formation & geological history
Formed via secondary silica deposition in volcanic cavities, sedimentary beds, or hydrothermal veins. Subsequent erosion and water action stream-rounded the specimen into a pebble, while iron oxide stains developed within fractures and surface layers.
Uses & applications
Commonly used for lapidary work, tumbling, decorative landscaping, and by beginner rockhounds for collecting.
Geological facts
Yellow to orange-brown varieties of microcrystalline quartz are often called carnelian or sard when uniform, or simply iron-stained quartz pebbles when naturally weathered in rivers and beaches.
Field identification & locations
Identified by its waxy-to-glassy sheen, translucency, rounded smooth edges, and scratch resistance to standard steel. Commonly found in gravel bars, riverbeds, beaches, and glacial till.
