mineral

Botryoidal Quartz or Chalcedony

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale), Color: tan to creamy white, Luster: vitreous to waxy, Crystal structure: Trigonal (microcrystalline), Cleavage: none (conchoidal fracture), Specific Gravity: 2.65

Identified July 10, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: tan to creamy white, Luster: vitreous to waxy, Crystal structure: Trigonal (microcrystalline), Cleavage: none (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Formed via precipitation of silica-rich hydrothermal fluids in cavities or fractures within volcanic or sedimentary rocks, often creating these 'bumpy' botryoidal (grape-like) textures.

Uses & applications

Used for lapidary work, jewelry making, and as decorative display specimens for mineral collectors.

Geological facts

The term 'botryoidal' comes from the Greek word 'botrys', meaning a bunch of grapes. This specific bubbly habit occurs when the mineral grows around many nuclei at once.

Field identification & locations

Identify in the field by its hardness (will scratch glass), grape-like surface texture, and lack of crystal faces. Commonly found in Arizona, Mexico, and volcanic regions globally.