sedimentary

Chert (Yellow Jasper)

Microcrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 on Mohs scale. Color: Opaque yellow to mustard brown with waxy luster. Physical properties: Conchoidal fracture, smooth texture, very fine-grained (microcrystalline).

Hardness: 6
Color: Opaque yellow to mustard brown with waxy luster

Identified May 31, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 on Mohs scale. Color: Opaque yellow to mustard brown with waxy luster. Physical properties: Conchoidal fracture, smooth texture, very fine-grained (microcrystalline).

Formation & geological history

Formed primarily through the chemical precipitation of silica-rich fluids in ocean environments or as nodules replacing limestone or chalk. Can occur in sedimentary layers of various geological ages from Precambrian to Cenozoic.

Uses & applications

Commonly used in lapidary work and jewelry when polished. Historically used by ancient civilizations for making tools like scrapers and arrowheads due to its sharp edges when broken.

Geological facts

Yellow jasper is often associated with the solar plexus chakra in metaphysical beliefs. Despite its name, it is chemically identical to flint and agate, differing mostly in its formation environment and opaque color.

Field identification & locations

Identify in the field by its waxy-to-dull luster, smooth feel, and conchoidal (shell-like) fracture patterns. It is frequently found in riverbeds, glacial tills, and desert pavements worldwide.