Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Scepter Quartz
Quartz with a wider crystal 'cap' that grew over a narrower stem, forming a natural scepter or mushroom shape.
crystal
Tangerine Quartz
Clear quartz coated with orange-red hematite, giving points a vivid tangerine color, mainly from Brazil.
crystal
Strawberry Quartz
A pink-to-red quartz colored by iron oxide inclusions that create a speckled, strawberry-like appearance within clear crystal.
crystal
Snow Quartz
An opaque, snow-white variety of quartz whose milky color comes from countless tiny gas and fluid inclusions.
crystal
Smoky Quartz
The smoky brown to gray variety of quartz, colored by natural irradiation, valued as both a gemstone and crystal specimen.
crystal
Rose Quartz
The soft pink, usually cloudy variety of quartz colored by trace titanium or microscopic inclusions, popular for carvings and beads.
crystal
Quartz Arenite
A clean, mature sandstone made almost entirely of quartz grains, representing extreme weathering, sorting, and recycling of sediment.
sedimentary
Quartz Schist
A foliated metamorphic rock dominated by quartz with enough mica to give it a schistose, splitting fabric.
metamorphic
Morion Quartz
The darkest, near-opaque black variety of smoky quartz, colored by natural radiation acting on trace aluminum.
crystal
Milky Quartz
The most common variety of quartz, milky white from microscopic fluid and gas inclusions, forming massive veins worldwide.
crystal
Lithium Quartz
A quartz crystal containing pink to lilac lithium-bearing mineral inclusions that give a soft cloudy lavender or rose coloration.
crystal
Lemon Quartz
A vivid greenish-yellow quartz, usually heat-treated or irradiated, prized for its clean clarity and bright lemon color.
crystal
Dumortierite Quartz
Quartz colored blue by inclusions of the mineral dumortierite, giving a denim-like blue ornamental stone harder than dumortierite alone.
gemstone
Cactus Quartz
A South African quartz whose central crystal is coated in a cactus-like crust of tiny secondary points, also called spirit quartz.
crystal
White Agate
A white to grayish banded chalcedony, the natural base color of much agate and the substrate for many dyed stones.
gemstone
Turritella Agate
A brown fossiliferous chalcedony packed with spiral freshwater snail shells, technically agatized fossil rock from Wyoming.
sedimentary
Scenic Agate
A translucent agate whose mineral inclusions resemble miniature landscapes of trees, hills, and horizons within the stone.
gemstone
Ruin Agate
A fractured and re-cemented agate whose angular broken bands resemble crumbling walls and ruined cityscapes when polished.
gemstone
Red Agate
A red-toned banded chalcedony colored by iron oxides, ranging from natural carnelian-like reds to heat-treated stones.
gemstone
Purple Agate
A purple-toned banded chalcedony, sometimes naturally amethystine but frequently produced by dyeing gray agate.
gemstone
Pink Agate
A soft pink banded chalcedony, occurring naturally in delicate hues and also commonly produced by dyeing.
gemstone
Iris Agate
A banded agate that diffracts transmitted light into rainbow colors when cut thin and backlit, producing a spectacular iridescence.
gemstone
Eye Agate
A chalcedony agate marked by round, concentric ring patterns that resemble eyes when cut and polished.
gemstone
Fortification Agate
The classic agate pattern of angular concentric bands resembling the walls of a fort, found in agates worldwide.
gemstone