Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Starburst Agate
Agate containing radiating sprays of mineral needles that fan out like bursting stars within the chalcedony.
gemstone
Spherulitic Obsidian
Obsidian containing spherulites — small radiating spheres of feldspar and cristobalite that crystallized within the cooling volcanic glass.
igneous
Sweetwater Agate
A translucent Wyoming chalcedony filled with delicate black manganese dendrites that resemble tiny ferns, moss, or starbursts.
gemstone
Lizard Skin Jasper
A patterned jasper whose scaly, net-like markings recall reptile skin, popular with lapidaries for its organic camouflage look.
gemstone
Cobra Jasper
A banded jasper with cream, tan, and brown layers resembling snakeskin, often sourced from Madagascar.
mineral
Dalmatian Jasper
A cream-colored spotted stone resembling a Dalmatian dog, made of feldspar and quartz dotted with dark mineral grains.
igneous
Silver Leaf Jasper
A gray-toned jasper with swirling cream, black, and brown leaf-like patterns, sometimes with druzy or agate pockets.
mineral
Bird's Eye Jasper
A microcrystalline quartz jasper marked by small concentric ring or eye patterns that resemble the eyes of birds.
mineral
Poppy Jasper
An orbicular jasper with red and orange flower-like spots resembling poppies, famously from Morgan Hill, California.
mineral
Star Moonstone
A rare moonstone that shows a four-rayed star of light (asterism) across its domed surface along with adularescence.
gemstone
Cloud Agate
A chalcedony agate with soft, billowing cloud-like masses of gray and white suspended in a translucent body.
gemstone
Tree Agate
A white chalcedony filled with green or black dendritic, tree-like mineral inclusions that resemble ferns or moss frozen in stone.
gemstone
Sunset Agate
A warmly colored chalcedony agate with reds, oranges, golds, and pinks that blend like the glowing bands of a sunset sky.
gemstone
Honey Agate
A warm golden to amber translucent chalcedony agate whose color and glow resemble honey, sometimes with banding.
gemstone
Frost Agate
A pale chalcedony agate with cloudy, frost-like white patterning suggesting frost on a window or icy crystalline textures.
gemstone
Flame Agate
A chalcedony agate with red, orange, and yellow plume or banding patterns that rise like dancing flames within the stone.
gemstone
Polyhedroid Agate
A rare agate that forms naturally with flat polygonal faces and angular geometric shapes rather than the usual rounded nodule.
gemstone
Zebra Agate
A banded chalcedony agate with bold alternating dark and light stripes resembling zebra markings, sometimes color-enhanced.
gemstone
Noreena Jasper
A rare Australian jasper from the Pilbara with bold red, yellow, and black abstract patterns, prized by collectors.
mineral
Brecciated Jasper
A jasper made of angular fragments naturally cemented back together, typically showing red and brown pieces in a quartz matrix.
sedimentary
Prehnite
A translucent yellow-green silicate famous for its botryoidal 'grape' clusters, often hosting needle-like sprays of black epidote.
mineral
Woodward Ranch Agate
Plume and fortification agate from the famous Woodward Ranch near Alpine, Texas, known for red and pink plumes.
gemstone
Seam Agate
Agate that forms in flat cracks or veins of host rock rather than rounded nodules, producing straight, parallel banding.
gemstone
Queensland Agate
Banded agate from Queensland, Australia, including the famous Agate Creek field, known for vivid fortification patterns.
gemstone