Agate (specifically Botswana or Lake Superior style Agate)

Physical Properties

Hardness: 6.5-7 on Mohs scale. Color: Banded layers of brown, orange, peach, and white. Luster: Waxy to vitreous. Crystal Structure: Hexagonal (microcrystalline). Cleavage: None (conchoidal fracture). Specific Gravity: 2.58-2.64.

Formation & Geological History

Formed in cavities (vesicles) of volcanic or metamorphic rocks. As mineral-rich silica groundwater seeps into these cavities, it deposits layers of microcrystalline quartz over thousands of years, creating the characteristic banding.

Uses & Applications

Commonly used in jewelry (cabochons), interior decoration, precision pendulums, and as metaphysical 'healing' stones. In industry, it is used for mortars and pestles because of its hardness.

Geological Facts

Agates are named after the Achates River in Sicily. They are known as the 'earth rainbow' because the concentric bands can represent almost every color that the earth can produce.

Field Identification & Locations

Identify in the field by looking for a 'waxy' appearance on broken surfaces and concentric banding patterns. They are frequently found on beaches or in riverbeds where volcanic rocks have eroded.

Identified on: 4/22/2026

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