Pumice
Pumice (volcanic rock)
Igneous
Category
Sedimentary And Igneous (Mixed)
Browse sedimentary and igneous (mixed) specimens identified by the Rock Identifier community.
Quartz Pebble
Silicon Dioxide (SiO2)
Mineral / Sedimentary occurrence
Marble
Metamorphosed Limestone/Dolomite
metamorphic
Quartz Pebble
Silicon Dioxide (SiO2)
Mineral / Sedimentary component
Limonite (Iron Ore/Hydrated Iron Oxide)
Limonite (mixture of FeO(OH)·nH₂O minerals, mainly Goethite, FeO(OH) and Lepidocrocite, FeO(OH))
Mineral
Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Banded Gneiss
Gneiss (variable mineral composition)
metamorphic
Quartz (Rock Crystal) with minor impurities
Quartz (SiO2)
Mineral
Chalcopyrite
Chalcopyrite (CuFeS2)
Mineral
Blue Quartz
Quartz (SiO2) with inclusions
Mineral
Orthoclase Feldspar (or K-Feldspar)
Orthoclase (KAlSi3O8)
Mineral
Granite
Granite (a plutonic igneous rock composed of quartz, feldspar, and mica)
igneous
Jasper in Basalt Matrix
Silicon Dioxide (SiO2) with impurities; Chalcedony
sedimentary (secondary mineral) within igneous
Quartz (on matrix)
Quartz (Silicon Dioxide, SiO₂)
Mineral
Schist
Schist (various mineralogical compositions including mica, chlorite, talc, etc.)
Metamorphic
Quartz (Float/Abraded)
Quartz (SiO₂)
Mineral
Pyrite
Iron Pyrite (FeS2)
mineral
Quartz Pebble (Iron-stained)
Silicon Dioxide (SiO2)
Mineral / Sedimentary setting
Yellow Chalcedony
Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)
Mineral
Smoky Quartz
SiO2 (Silicon Dioxide)
Mineral
Amethyst
Quartz (SiO2) variety
Mineral
Calcite
Calcite (CaCO₃, Calcium Carbonate)
Mineral
Marble
Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).
Metamorphic Rock
Epidote (or Epidote-rich rock)
Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).
Mineral, often found in metamorphic rocks but also in sedimentary and igneous rocks
Quartz Geode
Silicon Dioxide (SiO2) in a Geode body
sedimentary or igneous (host environment)
Milky Quartz
Quartz (SiO₂)
Mineral
Greenschist
Greenschist facies rock
Metamorphic
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety often found as a river rock)
Metamorphic Rock
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2
Mineral
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with impurities
sedimentary or igneous-associated mineral
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Mineral
Banded River Rock / Gneiss (highly weathered)
Gneiss
Metamorphic rock
Quartz (Crystal/Druzy Quartz)
Quartz (SiO₂)
Mineral
Quartz (likely)
Quartz (SiO2 - Silicon Dioxide)
Mineral
Quartz Geode (with Agate banding)
Silicon Dioxide (SiO2)
Sedimentary or Igneous (secondary formation)
Pyrite
Pyrite (Iron sulfide, FeS₂)
mineral
Green Aventurine
Aventurine (Silicon dioxide, SiO₂)
Mineral; variety of Quartz
Calcite
Calcite (Mineral, Calcium Carbonate - CaCO3)
Mineral
Banded Agate (variety of Chalcedony)
Agate (SiO2)
mineral
Quartz
Quartz (SiO2)
Mineral
Banded Gneiss
Gneiss (pronounced "nice")
metamorphic
Gneiss
Gneiss (a type of metamorphic rock)
Metamorphic Rock