Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Strontium Feldspar
Feldspar in which strontium dominates the large cation site, represented mainly by the rare mineral slawsonite.
mineral
Pezzottaite
A rare cesium-rich, beryl-related gem mineral with a raspberry-pink color, first found in Madagascar in 2002.
gemstone
Dalmatian Jasper
A cream-colored spotted stone resembling a Dalmatian dog, made of feldspar and quartz dotted with dark mineral grains.
igneous
Blue Jasper
An opaque blue variety of chalcedony jasper, less common than red or green forms, colored by mineral inclusions.
mineral
Vorobyevite
An old name for cesium-rich, often pink beryl (related to morganite), named after Russian mineralogist Victor Vorobyev.
gemstone
Feldspar
The most abundant mineral group in Earth's crust, feldspars are aluminosilicates that form much of granite and many igneous rocks.
mineral
Serpentine
A group of green magnesium silicate minerals with a smooth, waxy feel, often carved and sometimes sold as imitation jade.
mineral
Nephrite
One of the two jade minerals, an amphibole prized for its extreme toughness and soft, waxy green hues used in carving for millennia.
gemstone
Travertine
A banded, porous limestone deposited by mineral springs, prized as a warm-toned natural building and tile stone.
sedimentary
Pink Emerald
A trade name sometimes used for pink beryl (morganite), the manganese-colored rose-to-peach variety of the emerald mineral.
gemstone
Gneiss
A high-grade metamorphic rock defined by alternating light and dark mineral bands, formed under intense heat and pressure.
metamorphic
White Beryl
The colorless to milky-white variety of beryl, known mineralogically as goshenite and once used to imitate diamond and other gems.
gemstone
Shattuckite
A rare deep-blue copper silicate mineral, often fibrous or massive, named for the Shattuck Mine in Arizona and prized by collectors.
mineral
Howlite
A white, porous borate mineral webbed with gray-black veins, widely dyed to imitate turquoise and other stones.
mineral
Sulfur
A bright yellow native element mineral that forms around volcanic vents and hot springs and burns with a blue flame.
mineral
Malachite
A vivid green copper carbonate mineral famous for swirling concentric bands, used as an ore of copper and an ornamental gemstone.
mineral
Pyrrhotite
A bronze-colored iron sulfide notable for being the most magnetic of the common sulfide minerals and an important nickel host.
mineral
Siderite
Siderite is an iron carbonate ore, a brown rhombohedral mineral of the calcite group found in sediments and veins.
mineral
Vanadinite
A brilliant orange-red lead vanadate mineral forming hexagonal crystals, prized by collectors and mined as an ore of vanadium.
mineral
Calc-schist
A foliated metamorphic rock of calcite mixed with mica, quartz, and calc-silicate minerals, derived from marly sediments.
metamorphic
Sodalite
A royal-blue feldspathoid mineral with white calcite veining, often confused with lapis lazuli but lacking its golden pyrite flecks.
mineral
Bumblebee Jasper
A vivid yellow-and-black banded stone from Indonesian volcanic vents, colored by sulfur, arsenic minerals and iron oxides, not true jasper.
sedimentary
Metagabbro
Coarse-grained gabbro that has been metamorphosed, partly recrystallizing into amphibole, plagioclase, and other metamorphic minerals.
metamorphic
Mica
A family of sheet silicate minerals that split into thin, flexible, shiny sheets, giving rocks a sparkling, layered appearance.
mineral