Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
White Garnet
The rare colorless-to-white grossular garnet, also called leuco garnet, prized by collectors for its purity and unusual lack of color.
gemstoneHoney Garnet
A warm golden-brown garnet named for its honey color, typically a hessonite grossular variety with a distinctive treacly internal texture.
gemstoneTanzanite
A blue-violet zoisite found only in Tanzania, famous for its vivid trichroic color and rarity.
gemstoneAquamarine
The serene blue-to-sea-green variety of beryl, aquamarine is a durable gemstone colored by trace iron and birthstone for March.
gemstoneRosolite Garnet
A rose-pink variety of grossular garnet from Mexico, also known as landerite or xalostocite, prized for its soft pink color.
gemstoneLeuco Garnet
The rare colorless variety of grossular garnet, a near-flawless transparent gem free of the iron and chromium that color most garnets.
gemstoneTsavorite Garnet
A brilliant green grossular garnet colored by chromium and vanadium, rivaling emerald with superior brilliance and durability.
gemstoneDemantoid Garnet
A rare green andradite garnet famed for fire exceeding diamond and distinctive horsetail inclusions in Russian stones.
gemstoneBlack Garnet
An opaque black garnet — typically titanium-bearing melanite andradite — historically cut for mourning and Victorian jewelry.
gemstoneYellow Garnet
A trade term for yellow garnets, including golden grossular, yellow andradite (topazolite), and yellow-green Mali garnet.
gemstoneRainbow Obsidian
A black volcanic glass that reveals concentric rainbow bands of color when cut and polished against the light.
igneousGreen Agate
A green-hued banded chalcedony, ranging from natural soft greens to brightly dyed commercial stones.
gemstoneFairburn Agate
The state gemstone of South Dakota, a rare fortification agate known for tight, holly-leaf concentric banding.
gemstoneCrazy Lace Agate
A Mexican banded agate famous for tightly swirling, contorted lacy patterns in warm reds, creams, and golds.
mineralShadow Agate
A banded agate that displays a moving shadow or flash across its surface when tilted under light, caused by closely spaced parallel bands.
gemstoneCoyamito Agate
A prized banded agate from Rancho Coyamito in Chihuahua, Mexico, known for eyes, pom-poms and vivid fortification.
gemstoneCat's Eye Pink Tourmaline
Pink tourmaline cut en cabochon to reveal a moving band of light, a phenomenal gem colored by manganese with parallel inclusions.
gemstoneLaguna Agate
A highly prized Mexican fortification agate from Chihuahua, famed for vivid red and orange banding with tight, intricate patterns.
gemstoneCat's Eye Beryl
Beryl displaying chatoyancy, a bright moving band of light, caused by parallel tube-like inclusions when cut as a cabochon.
gemstoneCat's Eye Obsidian
Sheen obsidian cut so that aligned microscopic inclusions produce a single moving band of light, a cat's-eye effect.
igneousWehrite
An ultramafic rock of olivine and clinopyroxene, a peridotite variety common as cumulate layers in mafic intrusions.
igneousAchroite
The rare colorless variety of tourmaline, named from the Greek for 'without color' and prized by collectors.
gemstoneGoshenite Crystal
The pure colorless variety of beryl, valued as crystal specimens and as a brilliant alternative to clearer gemstones.
crystalCat's Eye Aquamarine
Aquamarine that shows a bright moving band of light, or cat's eye, caused by parallel needle-like inclusions when cut as a cabochon.
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