Rock Identifier
Yellow Jasper / Chalcedony (Silicon Dioxide (SiO2) with iron inclusions) — mineral
mineral

Yellow Jasper / Chalcedony

Silicon Dioxide (SiO2) with iron inclusions

Hardness: 6.5-7 Mohs scale. Color: Opaque to translucent brownish-yellow. Luster: Vitreous to waxy. Crystal structure: Trigonal/Microcrystalline. Cleavage: None (conchoidal fracture). Specific Gravity: 2.58–2.91.

Hardness
6
Color
Opaque to translucent brownish-yellow
Luster
Vitreous to waxy
Identified More mineral
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Physical properties

Hardness: 6.5-7 Mohs scale. Color: Opaque to translucent brownish-yellow. Luster: Vitreous to waxy. Crystal structure: Trigonal/Microcrystalline. Cleavage: None (conchoidal fracture). Specific Gravity: 2.58–2.91.

Formation & geological history

Formed through the deposition of silica-rich hydrothermal fluids in volcanic or sedimentary rock cavities. It is often found as secondary deposits in riverbeds or coastal environments.

Uses & applications

Used primarily in lapidary work, jewelry (beads and cabochons), ornamental carvings, and as a popular specimen for rock tumbling and crystal collecting.

Geological facts

Yellow Jasper was historically known as a 'protective stone' in ancient cultures. It gets its distinct yellow-brown hue from the presence of iron oxide (goethite) within the microcrystalline quartz structure.

Field identification & locations

Identify by its waxy luster, lack of cleavage, and extreme hardness (it will scratch glass). Commonly found in river gravels and beaches in regions with volcanic history or ancient sedimentary basins.