Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Smithsonite
Smithsonite is a zinc carbonate ore famous for glassy botryoidal crusts in blue-green, pink, and yellow hues.
mineralPyromorphite
A lead phosphate secondary mineral known for barrel-shaped green to yellow crystals formed in oxidized lead deposits.
mineralVanadinite
A brilliant orange-red lead vanadate mineral forming hexagonal crystals, prized by collectors and mined as an ore of vanadium.
mineralMillerite
A nickel sulfide famous for delicate brass-yellow hairlike crystals that form radiating sprays inside cavities and geodes.
mineralMacusanite
A rare translucent yellow-green volcanic glass from the Macusani region of Peru, valued by faceters and sometimes confused with tektites.
igneousWonderstone
A banded rhyolitic volcanic rock with swirling tan, red, and yellow iron-oxide layers prized as a decorative picture stone.
igneousLaguna Agate
A highly prized Mexican fortification agate from Chihuahua, famed for vivid red and orange banding with tight, intricate patterns.
gemstoneGarnet
A group of silicate gemstones best known for deep red but spanning nearly every color, including green tsavorite and orange spessartine.
gemstonePalagonite
A yellow-brown alteration material formed when basaltic volcanic glass reacts with water, common in hydrovolcanic tuffs and pillow lavas.
igneousPrehnite
A translucent yellow-green silicate famous for its botryoidal 'grape' clusters, often hosting needle-like sprays of black epidote.
mineralMookaite
A vivid Australian jasper-like silica stone in earthy reds, yellows, and purples, formed from silicified radiolarian sediment.
mineralOcean Jasper
A multicolored orbicular chalcedony from Madagascar famous for its circular eye-like orbs in greens, pinks, whites, and yellows.
sedimentaryLake Huron Agate
Glacially transported banded agates found along Lake Huron's shores, typically small, frosted pebbles with red-orange iron banding.
gemstoneBumblebee Jasper
A vivid yellow-and-black banded stone from Indonesian volcanic vents, colored by sulfur, arsenic minerals and iron oxides, not true jasper.
sedimentaryCat's Eye Opal
An opal cut to show chatoyancy, a sharp moving band of light like a cat's eye, usually in honey, green or yellow common opal.
gemstoneZincite
A rare zinc oxide best known for its deep red to orange color, classically from Franklin, New Jersey, and as colorful man-made crystals.
mineralChrysoprase
A translucent apple-green chalcedony colored by nickel, the most prized green variety of the quartz family.
gemstonePietersite
A brecciated, chatoyant quartz with swirling blue, gold, and brown fibers that shimmer like a stormy sky.
gemstoneBird's Eye Jasper
A microcrystalline quartz jasper marked by small concentric ring or eye patterns that resemble the eyes of birds.
mineralOnyx
A banded variety of chalcedony quartz, classically black or black-and-white, long favored for cameos and beads.
gemstoneAgate
A banded variety of chalcedony quartz, famed for its colorful concentric layers and enormous range of patterns and colors.
mineralThulite
A pink, manganese-rich variety of zoisite used as an ornamental gemstone, often mottled with white quartz and grey matrix.
gemstoneRutile
Rutile is a major titanium ore and the famous golden needle inclusion that gives rutilated quartz its shimmering threads.
mineralBrecciated Jasper
A jasper made of angular fragments naturally cemented back together, typically showing red and brown pieces in a quartz matrix.
sedimentary