Sandstone (River Rock)
Arenite (composed primarily of SiO2)
sedimentary
Category
Mineral Like Biological Tissue
Browse mineral like biological tissue specimens identified by the Rock Identifier community.
Apatite
Apatite Group (e.g., Fluorapatite Ca5(PO4)3F, Chlorapatite Ca5(PO4)3Cl, Hydroxylapatite Ca5(PO4)3(OH))
mineral
Iolite (Cordierite)
Magnesium Iron Aluminum Silicate (Mg,Fe)2Al4Si5O18
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone
Arenite (primarily Quartz, SiO2)
sedimentary
Mica Schist
Mica Schist (Composition typically contains Muscovite: KAl2(AlSi3O10)(OH)2 or Biotite: K(Mg,Fe)3AlSi3O10(OH)2 along with Quartz and Feldspar)
metamorphic
Jasper with Quartz Veining
Silicon Dioxide (SiO2) with impurities
sedimentary
Sunstone
Heliolite (Oligoclase or Orthoclase Feldspar), (Ca,Na)(Al,Si)4O8
mineral
Coarse Sandstone
Arenite (SiO2 based)
sedimentary
Magnetite
Iron(II,III) oxide (Fe3O4)
mineral
Sandstone
Arenite (primarily Quartz, SiO2)
sedimentary
Gneiss
Gneiss (high-grade metamorphic rock typically composed of quartz, feldspar, and mica)
metamorphic
Cobaltian Calcite
Cobalt-bearing Calcite (Ca,Co)CO3
mineral
Amygdaloidal Basalt with Secondary Minerals
Basalt containing secondary mineralization (likely Chlorite, Celadonite, or Zeolites)
igneous
Mica Schist
Schist (primarily Muscovite and Biotite mica)
metamorphic
Common Opal
Hydrated Amorphous Silica (SiO2·nH2O)
mineraloid
Serpentinite
Serpentinite (composed primarily of serpentine-group minerals like antigorite, chrysotile, and lizardite; chemical formula varies but generally Mg3Si2O5(OH)4)
Metamorphic Rock
Quartz
Quartz (SiO₂)
mineral
Amphibolite with Hornblende
Amphibole-rich Metamorphic Rock (Ca2(Mg,Fe)5Si8O22(OH)2)
metamorphic
Conglomerate
Clastic sedimentary rock (Conglomerate)
sedimentary
Blue Calcite
Calcium Carbonate (CaCO3)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Green Druzy Quartz (Prasiolite)
Silicon Dioxide (SiO2) with inclusions (typically Chlorite or Actinolite)
mineral
Sandstone (Ferruginous)
Arenite (Fe-oxide cemented)
sedimentary
Granite Gneiss
Felsic Gneiss
metamorphic
Garnet Schist
Garnetiferous Mica Schist
metamorphic
Chert (Jasper variety)
Chert (SiO2)
sedimentary
Sandstone (Banded)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Granite Pegmatite with Tourmaline and Muscovite
Pegmatite (Feldspar: KAlSi3O8, Quartz: SiO2, Schorl: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH))
igneous
Milky Quartz Pebble (Iron-Stained)
Silicon Dioxide (SiO2)
mineral
Diorite (Salt and Pepper Rock)
Diorite
igneous
Granitic Gneiss
Gneiss (Metamorphic rock of granitic composition)
metamorphic
Vesicular Basalt (or Porphyritic Scoria)
Vesicular Basalt
igneous
Botryoidal Goethite
Goethite (α-Fe3+O(OH))
mineral
Sandstone
Arenite (primarily SiO2)
sedimentary
Yellow Ochre / Limonite
Limonite (FeO(OH)·nH2O)
Mineral
Granitic Pegmatite
Coarse-grained Granite (KAlSi3O8 + SiO2)
igneous
Quartz (Milky to Clear)
Silicon Dioxide (SiO2)
mineral
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Sandstone (Ferruginous/Banded)
Clastic Terrigenous Sandstone (SiO2 with Fe2O3 cement)
sedimentary
Smoky Quartz
Smoky Quartz (SiO2: Silicon Dioxide)
mineral
Dendritic Agate
Silicon Dioxide (SiO2) with manganese/iron inclusions
mineral