Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Pyrargyrite
A silver antimony sulfosalt known as dark ruby silver, an important silver ore with deep red internal reflections.
mineralMaxixe
A deep blue beryl with a color caused by radiation that fades in light, named after the Maxixe mine in Brazil.
gemstone
Aventurine
A translucent quartz speckled with glittery mineral inclusions that produce a shimmering aventurescence, most often green.
crystalDragon Vein Agate
A treated chalcedony with a network of crackled veins, usually heated and dyed in vivid colors for affordable, eye-catching beads.
gemstoneAmegreen
A natural bicolor quartz blending amethyst purple with prasiolite green in a single crystal, prized as a metaphysical heart-crown stone.
crystalSonoran Sunset Jasper
A vivid copper-bearing Mexican stone of red cuprite and green chrysocolla that evokes a desert sunset.
mineral
Black Opal
The rarest and most valuable opal, with a dark body tone that makes its flashing rainbow play-of-color blaze brilliantly.
gemstone
Feldspathic Sandstone
A feldspar-rich sandstone, often pink, that points to granitic source rocks eroded quickly in dry or cold climates.
sedimentaryRibbon Jasper
A banded jasper showing parallel ribbon-like stripes of contrasting color formed by layered silica and mineral deposition.
mineral
Latite
The fine-grained volcanic equivalent of monzonite, an intermediate lava with nearly equal feldspars and little free quartz.
igneousSardonyx
A banded chalcedony combining reddish-brown sard with white or black onyx layers, prized since antiquity for carved cameos.
gemstoneKiwi Jasper
A speckled green-and-black stone resembling kiwi fruit, technically a quartz-amazonite aggregate rather than true jasper.
mineralNordmarkite
A light-colored alkali quartz syenite dominated by perthitic feldspar with minor quartz, from the Oslo igneous province of Norway.
igneousMidnight Lace Obsidian
A black volcanic glass threaded with delicate grey, swirling lace-like bands of flow lines that show beautifully when polished.
igneousUrtite
A pale, nepheline-dominated plutonic rock at the leucocratic end of the ijolite series, sometimes associated with major apatite ore deposits.
igneous
Brandberg Amethyst
A prized Namibian quartz combining amethyst, smoky, and clear quartz in single crystals, often with phantoms and enhydros.
crystalSuper Seven
A trade name for quartz containing a combination of seven minerals including amethyst, smoky quartz, and cacoxenite, prized by collectors.
crystalFeather Jasper
A jasper marked with soft feather- or plume-like mineral inclusions that drift through a pale silica body.
mineralDendritic Jasper
A pale jasper threaded with black, fern-like mineral dendrites that mimic plants, trees, and frost despite being inorganic.
mineral
Graphic Feldspar
A pegmatite rock of feldspar intergrown with wedge-shaped quartz that resembles ancient runic or Hebrew writing.
igneous
Monzonite
An intermediate plutonic rock with nearly equal alkali and plagioclase feldspar and very little quartz, sitting between diorite and syenite.
igneousGary Green Jasper
An Oregon jasper, also called larsonite, of silicified fossil wood showing olive-green fields laced with black dendritic patterns.
mineral
Spherulitic Obsidian
Obsidian containing spherulites — small radiating spheres of feldspar and cristobalite that crystallized within the cooling volcanic glass.
igneous
Needle Tourmaline
Fine acicular (needle-like) tourmaline crystals, often black schorl, frequently seen as slender inclusions within clear quartz.
mineral