Basalt
Basalt (Extrusive Mafic Igneous)
Category
Browse sedimentary rock or mineral (depending on origin and purity) specimens identified by the Rock Identifier community.
Basalt
Basalt (Extrusive Mafic Igneous)
Dalmatian Jasper (Dalmatian Stone)
Perthitic feldspar with Arfvedsonite inclusions
Clear Quartz
Silicon Dioxide (SiO2)
Emerald
Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities
Amethyst and Citrine (Ametrine Mix)
Silicon Dioxide (SiO2) with Fe3+ impurities
White Marble
Calcite-rich Metasomatized Carbonate (CaCO3)
Hypersthene
Hypersthene ((Mg,Fe)SiO₃)
Granite (Specimen: Logan Rock)
Phaneritic plutonic igneous rock (mainly Quartz, Feldspar, and Mica)
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) in matrix
Kyanite (in Schist Matrix)
Kyanite (Al2SiO5)
Green Calcite
Calcium Carbonate (CaCO3)
Quartzite
Quartzite (SiO2)
Gypsum (Wallboard/Drywall)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
Chalcedony Nodule (Carnelian/Agate)
Chalcedony (Silicon Dioxide, SiO2)
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
White Quartz (Milky Quartz)
Quartz (Silicon Dioxide - SiO2)
Chrome Diopside
Magnesium Calcium Silicate (MgCaSi2O6) containing Chromium impurities
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Granite
Phaneritic Igneous Rock (Granite)
Metal Chain (Likely Steel or a Steel Alloy)
Steel (primarily iron and carbon); specific alloy unknown
Diorite
Intermediate plutonic igneous rock
Quartzite (River Pebble)
Recrystallized Quartz (SiO2)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Quartzite Pebble
Metamorphic Quartzite (SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Banded Iron Formation (BIF)
Banded Iron Formation
Clear Quartz (Crystal Quartz)
Silicon Dioxide (SiO2)
Quartz (Smoky Quartz variant)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO₂)
Chalcedony (Commonly known as Carnelian or Agate pebble)
Microcrystalline Quartz (SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Jasper
Silicon dioxide (SiO2)
Granite / Gneiss Complex
Felsic Plutonic Rock (Granite) or High-grade Metamorphic Rock (Gneiss)
Agate
Agate (a variety of Chalcedony, SiO2)
Basalt with Olivine Phenocrysts
Porphyritic Basalt (containing Mg2SiO4 - Fe2SiO4)
Amethyst
SiO2 (Silicon Dioxide with Iron impurities)
Native Gold Nugget
Native Gold (Au)
Fulgurite
Fulgurite (Lechatelierite), amorphous SiO2
Quartzite River Pebble
Quartzite (primarily Silicon Dioxide, SiO2)
Lapis Lazuli
Lazurite-rich metamorphic rock ((Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)