Rock & Mineral Encyclopedia
Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.
Pyrite
The brassy iron sulfide mineral famous as 'fool's gold,' known for sharp metallic cubes and a much higher hardness than real gold.
mineral
Peacock Ore
A copper-iron sulfide ore famous for its iridescent peacock-like purple and blue tarnish; often sold as treated chalcopyrite.
mineral
Chalcopyrite
A brassy copper-iron sulfide that is the world's most important copper ore, often showing colorful iridescent tarnish.
mineral
Arsenopyrite
A silver-white iron arsenic sulfide and the most common arsenic mineral, known for striking sparks and a garlic smell when struck.
mineral
Pyrrhotite
A bronze-colored iron sulfide notable for being the most magnetic of the common sulfide minerals and an important nickel host.
mineral
Bornite
A copper iron sulfide famous for its vivid iridescent purple-blue tarnish, the classic peacock ore and a copper ore.
mineral
Galena
A heavy, lead-grey metallic mineral with perfect cubic cleavage, galena is the world's main ore of lead and often carries silver.
mineral
Ironstone
An iron-rich sedimentary rock, often heavy and rusty-weathering, historically mined as a major source of iron ore.
sedimentary
Blue Beryl
The blue color variety of beryl, ranging from pale sky tones to rich sea-blue, best known in its finest grades as aquamarine.
gemstone
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
Millerite
A nickel sulfide famous for delicate brass-yellow hairlike crystals that form radiating sprays inside cavities and geodes.
mineral
Molybdenite
Molybdenite is the primary ore of molybdenum, a soft, greasy, silver-gray sulfide that closely resembles graphite.
mineral
Bismuthinite
A soft lead-gray bismuth sulfide that is an important ore of bismuth, forming metallic needle-like and bladed crystals.
mineral
Patronite
A rare greenish-black vanadium sulfide that was historically one of the world's most important ores of vanadium.
mineral
Cinnabar
A bright red mercury sulfide, the chief ore of mercury and the historic source of the pigment vermilion.
mineral
Bronzite
An iron-rich orthopyroxene prized for its warm bronze schiller, a metallic-looking sheen created by tiny mineral inclusions.
mineral
Stibnite
Stibnite is the chief ore of antimony, famous for its dramatic clusters of bladed, silvery-gray metallic crystals.
mineral
Mustard Jasper
A warm mustard-to-ochre yellow jasper colored by iron, valued by lapidaries for its rich, earthy golden tone.
gemstone
Acanthite
A silver sulfide that is one of the most important silver ore minerals, forming dark metallic crystals and wires.
mineral
Stephanite
A black metallic silver antimony sulfide, historically a notable silver ore known as brittle silver ore.
mineral
Chalcocite
A dark gray copper sulfide that is one of the richest copper ores, prized by collectors when found as rare sharp crystals.
mineral
Proustite
A scarlet-red silver arsenic sulfide known as light ruby silver, a striking but light-sensitive ore that darkens on exposure.
mineral
Hyalophane
A barium-bearing potassium feldspar intermediate between orthoclase and celsian, found in barium-rich metamorphic and ore deposits.
mineral
Pyrargyrite
A silver antimony sulfosalt known as dark ruby silver, an important silver ore with deep red internal reflections.
mineral