Rock & Mineral Encyclopedia

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

Cacholong Opal

An opaque, porcelain-white common opal prized for its milky, pearl-like appearance and high porosity, often carved or beaded.

The classic agate defined by concentric or parallel bands of chalcedony in varied colors, the archetype of all agate varieties.

A chalcedony agate marked by round, concentric ring patterns that resemble eyes when cut and polished.

A translucent chalcedony from Montana filled with black and red dendritic inclusions that look like moss, ferns, or scenic landscapes.

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

A transparent to milky opal that displays a soft bluish-white internal glow or sheen that seems to follow the light source.

An opaque to translucent milky-white common opal valued for its soft porcelain-like color rather than play-of-color.

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

A soft sky-blue banded chalcedony prized for its delicate, lace-like white and blue swirling patterns.

A banded chalcedony with straight, ribbon-like parallel layers, often cut across the bands for striking striped cabochons.

A creamy pink-and-white chalcedony from Madagascar containing flower-like plume inclusions that resemble blossoms suspended in stone.

A red-toned banded chalcedony colored by iron oxides, ranging from natural carnelian-like reds to heat-treated stones.

A rare brown chalcedony containing thin iron-oxide layers that produce flashing, fiery rainbow iridescence like trapped flames.