Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Opalite
A man-made opalescent glass that glows milky blue in reflected light and warm orange when backlit, often sold as a crystal.
crystal
Goldstone
A man-made glittering glass packed with tiny copper crystals, traditionally reddish-brown but also made in blue and green.
crystal
Blue Goldstone
A man-made glittering glass colored deep blue with cobalt and studded with tiny copper crystals that mimic a starry night sky.
gemstone
Zincite
A rare zinc oxide best known for its deep red to orange color, classically from Franklin, New Jersey, and as colorful man-made crystals.
mineralMint Obsidian
A pale mint-green glass sold as obsidian; most uniform light-green material on the market is manufactured glass rather than natural volcanic obsidian.
igneousBlue Obsidian
Blue-colored volcanic glass; genuine natural blue obsidian is very rare, while much blue obsidian on the market is manufactured glass.
crystal
Green Obsidian
Green-tinted volcanic glass; some is naturally colored by trace iron, but vivid emerald-green pieces are usually manufactured glass.
crystalCrimson Obsidian
A deep red glass sold as obsidian; vivid uniform crimson material is usually manufactured glass rather than natural volcanic obsidian.
igneousCherry Obsidian
A vivid cherry-red glass sold as obsidian; the bright transparent red color is manufactured, as natural obsidian only shows dull red-brown mahogany tones.
igneousViolet Obsidian
A violet-to-purple glass sold as obsidian; uniform purple material is almost always manufactured glass rather than natural volcanic obsidian.
igneousCobalt Blue Obsidian
A deep cobalt-blue glass sold as obsidian; intense blue body color is manufactured, as natural obsidian does not form bright blue glass.
igneousTangerine Obsidian
A vivid orange glass sold as obsidian; uniformly bright tangerine material is typically manufactured glass rather than natural volcanic obsidian.
igneousEmerald Green Obsidian
A bright emerald-green glass sold as obsidian; saturated transparent green is manufactured, while rare natural green obsidian is only faintly tinted.
igneousLavender Obsidian
A soft lavender-purple glass sold as obsidian; uniform lavender material is essentially always manufactured glass, not natural volcanic obsidian.
igneousTeal Obsidian
A deep teal glass sold as obsidian; the saturated blue-green color is manufactured and not found in natural volcanic glass.
igneousLilac Obsidian
A soft pale-purple glass sold as obsidian; uniform lilac material is essentially always manufactured glass rather than natural volcanic obsidian.
igneousRoyal Blue Obsidian
A deep royal-blue glass sold as obsidian; the rich blue body color is manufactured, unlike natural blue-sheen obsidian whose blue is only a surface effect.
igneousPastel Obsidian
Soft pastel-colored glass sold as obsidian; multicolor pastel material is manufactured art glass rather than natural volcanic obsidian.
igneousStrawberry Obsidian
A pink-red glass sold as obsidian, sometimes with metallic flecks; the strawberry color is manufactured rather than a natural volcanic glass tone.
igneous
Yellow-Green Obsidian
A chartreuse yellow-green glass sold as obsidian; the bright color is manufactured and does not occur in natural volcanic glass.
igneousTurquoise Obsidian
A vivid turquoise-blue glass sold as obsidian; this bright color is virtually always manufactured rather than natural volcanic glass.
igneousWatermelon Obsidian
A pink-and-green bicolor glass sold as obsidian; the watermelon coloring is manufactured and does not occur in natural volcanic glass.
igneous
Purple Obsidian
Purple-colored volcanic glass; genuine natural purple obsidian is rare, with much purple obsidian being manufactured colored glass.
crystal
Lherzolite
The most common type of mantle peridotite, made of olivine with both orthopyroxene and clinopyroxene, representing fertile upper-mantle rock.
igneous