Black Marble
Recrystallized Calcite (CaCO3)
metamorphic
Category
Mineral Description (Anthropogenic Material)
Browse mineral description (anthropogenic material) specimens identified by the Rock Identifier community.
Learn about Mineral Description (Anthropogenic Material) in the encyclopedia
View all →
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Chert (or Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Quartzite
Quartzite (primarily SiO2)
metamorphic
Limestone
Limestone (Calcium Carbonate, CaCO3)
Sedimentary
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3/FeO(OH) cementing agents)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Red Sandstone
Arenite (Fe2O3 rich)
sedimentary
Quartz Vein in Host Rock (Breccia/Rhyolite)
Silicon Dioxide (SiO2) with matrix
Mineral in Igneous/Sedimentary host
Greenschist
Greenschist (containing Chlorite, Epidote, and Actinolite)
metamorphic
Fossilized oyster or bivalve shell
Fossil Gryphaeidae or Ostreoidea; calcitic shell, CaCO₃
fossil
Banded Gneiss
Gneiss (Metamorphic high-grade rock)
metamorphic
Man-made Synthetic Material (Plastic/Composite)
Acrylonitrile Butadiene Styrene (ABS) or High-Impact Polystyrene (HIPS)
Non-geological / Synthetic
Shale
Argillaceous Sedimentary Rock
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (High Silica / Iron Oxide)
sedimentary
Sandstone (Ferruginous)
Arenite (SiO2 with Iron Oxide impurities)
sedimentary
Garnet-bearing gneiss
Quartz–feldspar–mica gneiss with iron-rich garnet (commonly almandine)
metamorphic
Fossil shell fragment
Likely a fossilized brachiopod or bivalve; exact taxon cannot be determined from the image
fossil
Sandstone (Banded)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Fossil-bearing sedimentary rock, possibly fossil wood or bone
Indeterminate silicified/carbonate fossil in sandstone or mudstone
fossil
Petrified Wood
Silicified Wood (Permineralized organic matter, głównie $SiO_2$)
fossil
Fossilized Horse Tooth
Equus sp. (fossilized molar)
fossil
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
fossil
Chert (Septarian Nodules-like)
Silicon dioxide (SiO2)
sedimentary
Ironstone Concretion (Boxwork)
Siderite-Limonite Concretion (FeO(OH)·nH2O)
sedimentary
Fulgurite
Lechatelierite (Fused Silica)
mineral
Quartz-rich rock fragment
Microcrystalline quartz (SiO₂), possibly chalcedony or quartz-bearing breccia
mineral
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Amygdaloidal Basalt
Basalt with secondary mineral infillings (SiO2, (Ca,Na)2-3(Mg,Fe,Al)5Si8O22(OH)2)
igneous
Iron-rich sulfide ore, likely pyrite-bearing gossan
Pyrite (FeS₂), possibly mixed with iron oxides/hydroxides and other sulfides
mineral
Blue glass-like tumbled specimen
Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image
mineral
Polished orbicular granite (likely K2-type granite)
Granite, chiefly quartz, alkali feldspar, plagioclase, and dark amphibole/biotite; possible epidote-rich orbicules
igneous
Slate
Metamorphic Mudstone / Shale
metamorphic
Rose Quartz (carved cutlass pendant)
Silicon Dioxide (SiO2)
gemstone
Chert / Flint
Silicon Dioxide (SiO2)
sedimentary
Shale with Trace Fossils
Fissile mudrock (Shale)
sedimentary
Diorite
Phaneritic intermediate plutonic rock
igneous
Mica-rich granite (likely biotite granite)
Biotite granite; mainly quartz (SiO₂), alkali/feldspar, and biotite mica
igneous
Coquina
Biogenic Limestone (Calcite/Aragonite base, CaCO3)
sedimentary
Greenish Metamorphic Rock (likely containing epidote or chlorite)
Metamorphic rock, possibly epidosite or greenstone
Metamorphic
Septarian Nodule (Galt)
Calcareous concretion / Septarian concretion
sedimentary
Petrified wood
Silicified wood, chiefly microcrystalline quartz (SiO₂)
fossil