mineral

Grape Agate

Botryoidal Amethystine Chalcedony (SiO2)

Hardness: 6.5-7 (Mohs scale), Color: Purple to violet, Luster: Vitreous to waxy, Crystal structure: Trigonal (microcrystalline), Cleavage: None, Specific gravity: 2.60-2.65

Hardness: 6

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 6.5-7 (Mohs scale), Color: Purple to violet, Luster: Vitreous to waxy, Crystal structure: Trigonal (microcrystalline), Cleavage: None, Specific gravity: 2.60-2.65

Formation & geological history

Formed through hydrothermal processes in volcanic cavities. The grape-like spheres are botryoidal formations of chalcedony that occurred during the Cenozoic era, typically in andesite or basalt host rocks.

Uses & applications

Primarily used as a mineral specimen for collectors, in metaphysical practices, and occasionally carved into ornamental jewelry pieces.

Geological facts

Despite its name, it is technically a form of chalcedony rather than a true banded agate. It was only recently discovered and brought to the international market around 2016.

Field identification & locations

Identified by its distinctive purple color and 'botryoidal' (cluster of grapes) texture. Most high-quality specimens are found in the Mamuju region of West Sulawesi, Indonesia.