Fossilized Crab Carapace (Concretion)
Decapoda (fossil), typically preserved in calcite or siderite concretion
sedimentary
Category
Igneous, Sedimentary, Or Metamorphic (Mineral Based)
Browse igneous, sedimentary, or metamorphic (mineral based) specimens identified by the Rock Identifier community.
Learn about Igneous, Sedimentary, Or Metamorphic (Mineral Based) in the encyclopedia
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Pyrite Nodules / Weathered Pyrite
Iron Sulfide (FeS2)
mineral
Milky Quartz Pebble
Crystalline Silicon Dioxide (SiO2)
mineral
Synthetic Wolf Plush (Non-mineral)
Canis lupus similis (Prop material: Polyester & Synthetic fibers)
Synthetic material/Textile
Quartzite Cobble
Quartzite (SiO2 based)
metamorphic
Porphyry (Flower Stone)
Porphyritic Basalt or Andesite
igneous
Sandstone (Quartzose)
Arenite (composed primarily of SiO2)
sedimentary
Mica Schist
Schist (Muscovite/Biotite Schist)
metamorphic
Likely raw mica-bearing metamorphic rock or mineral fragment
Tentatively biotite schist; visually similar dark mica-rich material
metamorphic
Epidote (likely Unakite component or Epidosite)
Epidote (Ca2(Al2Fe)(SiO4)(Si2O7)O(OH))
metamorphic
Labradorite
(Na,Ca)(Al,Si)4O8
mineral
Tumbled orbicular jasper
Orbicular jasper; microcrystalline quartz (SiO₂) with iron oxides and feldspathic/chalcedony inclusions
sedimentary
Quartzite river stone
Quartzite (SiO2)
metamorphic
Dyed Agate Slice
Chalcedony (Silicon Dioxide, SiO2) with artificial pigment
mineral
Breccia
Breccia - Clastic sedimentary rock
sedimentary
Pyrite-bearing schist (likely mica schist)
Muscovite–quartz schist with disseminated pyrite (FeS₂)
metamorphic
Feldspar
Feldspar (Orthoclase/Microcline)
mineral
Clear Quartz
Silicon Dioxide (SiO2)
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Muscovite Mica
Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2
mineral
Citrine
Silicon dioxide (SiO2)
mineral
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Marble
Metamorphic rock composed of Recrystallized Carbonate Minerals (chiefly CaCO3)
metamorphic
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(F,OH)2)
mineral
Sandstone
Arenite (SiO2 based clastic rock)
sedimentary
Leopardite
Quartz porphyry / Quartz monzonite with manganese oxide spots
igneous
Muscovite Mica
Muscovite (KAl2(AlSi3O10)(OH)2)
mineral
Calcite crystal cluster
Calcite (calcium carbonate, CaCO₃)
mineral
Sandstone with Secondary Mineral Encrustation
Arenite with Silica/Calcite deposits (SiO2 or CaCO3)
sedimentary
Blue Apatite
Ca5(PO4)3(F,Cl,OH)
mineral
Gneiss
Gneiss
metamorphic
Epidote
Epidote {Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)
mineral
Quartz-rich metamorphic rock, likely quartzite
Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with mica or iron-oxide impurities
metamorphic
Pebble
Lithified clastic rock fragment / Quartz-rich pebble
sedimentary
Diorite
Diorite (Intermediate intrusive igneous rock)
igneous
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Green Moss Agate
Silicon Dioxide (SiO2) with Mineral Inclusions
sedimentary
Sandstone
Arenite (mostly Quartz-based)
sedimentary
Biotite in Host Matrix
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
mineral
Biotite-bearing gneiss or schist
Quartz–feldspar–mica metamorphic rock, likely mica schist/gneiss
metamorphic
Mica
Phlogopite or Biotite group (KMg3(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)
mineral
Quartz with Muscovite Mica
Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide Fluoride (KAl2(AlSi3O10)(F,OH)2)
mineral