Rock & Mineral Encyclopedia

Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.

Grape Agate

Clusters of tiny botryoidal chalcedony spheres resembling bunches of grapes, famously purple, found in Indonesia.

A purple-toned banded chalcedony, sometimes naturally amethystine but frequently produced by dyeing gray agate.

A chalcedony agate filled with radiating needle-like mineral inclusions, prized for its starburst and spray patterns.

A hollow rock nodule whose interior cavity is lined with inward-pointing crystals such as quartz, amethyst, or calcite.

Agate containing radiating sprays of mineral needles that fan out like bursting stars within the chalcedony.