Rock & Mineral Encyclopedia

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

Polychrome Jasper

A warm earth-toned jasper from Madagascar in flowing reds, oranges and golds, also called desert jasper, discovered in the early 2000s.

Obsidian colored brown by iron oxide inclusions, frequently banded or swirled with black as in mahogany obsidian.

Rhodochrosite is a rose-pink manganese carbonate prized for raspberry-red crystals and banded pink-and-white gem material.

A vividly banded fortification agate from Argentina prized for its bold red, gold and white concentric patterns.

A Mexican banded agate famous for tightly swirling, contorted lacy patterns in warm reds, creams, and golds.

A brownish-red to deep brown variety of chalcedony, closely related to carnelian but darker, colored by iron oxides.

A highly prized Mexican fortification agate from Chihuahua, famed for vivid red and orange banding with tight, intricate patterns.

A warmly colored chalcedony agate with reds, oranges, golds, and pinks that blend like the glowing bands of a sunset sky.

A chalcedony agate with red, orange, and yellow plume or banding patterns that rise like dancing flames within the stone.

A fractured and re-cemented agate whose angular broken bands resemble crumbling walls and ruined cityscapes when polished.