Rock & Mineral Encyclopedia

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

Sardonyx

A banded chalcedony combining reddish-brown sard with white or black onyx layers, prized since antiquity for carved cameos.

A rare, prized Oregon picture jasper known for blue-green orbs and scenic patterns, often called the king of jaspers.

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

An orbicular jasper with red and orange flower-like spots resembling poppies, famously from Morgan Hill, California.

A vivid blue-green hydrated copper silicate, soft on its own but prized as a gem when hardened by intergrown quartz or chalcedony.

A gray-toned jasper with swirling cream, black, and brown leaf-like patterns, sometimes with druzy or agate pockets.

A prized Mexican jasper known for pastel green, lavender, and cream orbicular patterns that take an exceptional polish.

A gray-brown jasper whose mottled, wrinkled patterning resembles elephant hide, also sold as Miriam or calligraphy stone.

A prized Idaho picture jasper from Bruneau Canyon known for brown and cream orbicular egg-rock patterns and scenic landscapes.

A dark green jasper-chalcedony speckled with red iron-oxide spots, classically known as bloodstone or heliotrope.

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

A regional Russian name for a moonstone-like plagioclase from the White Sea coast, prized for its bluish, slightly iridescent schiller.

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

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

A pink, manganese-rich variety of zoisite used as an ornamental gemstone, often mottled with white quartz and grey matrix.