mineral

Yellow Chalcedony / Yellow Agate

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs scale); Color: Yellow to translucent gold; Luster: Waxy to vitreous; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific gravity: 2.58-2.64

Hardness: 6
Color: Yellow to translucent gold
Luster: Waxy to vitreous

Identified July 18, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs scale); Color: Yellow to translucent gold; Luster: Waxy to vitreous; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific gravity: 2.58-2.64

Formation & geological history

Formed through the deposition of silica-rich groundwater in cavities of igneous and sedimentary rocks. Often found in volcanic geodes or as nodules in sedimentary layers.

Uses & applications

Used primarily in jewelry as cabochons (as seen in this wire-wrapped pendant), ornamental carvings, and for metaphysical purposes in the crystal healing community.

Geological facts

Yellow chalcedony belongs to the quartz family but has a microcrystalline structure, meaning its crystals are too small to see with the naked eye. It has been used for seals and jewelry since antiquity.

Field identification & locations

Identify by its waxy luster, translucency, and lack of visible crystal faces. It is common in riverbeds and volcanic areas in Brazil, India, and the Western USA. It will scratch glass but cannot be scratched by a steel knife.