Likely biotite-bearing metamorphic rock (schist or gneiss)
Mica schist/gneiss; chiefly quartz, feldspar, and biotite mica
Category
Browse sedimentary (man made) specimens identified by the Rock Identifier community.
Likely biotite-bearing metamorphic rock (schist or gneiss)
Mica schist/gneiss; chiefly quartz, feldspar, and biotite mica
Botryoidal chalcedony (possible seam agate)
Microcrystalline quartz, SiO₂; commonly with iron-oxide and clay inclusions
Water and Silt (Sedimentary Environment)
Suspended Sediment / H2O (dihydrogen monoxide)
Chert / Jasper
Microcrystalline Quartz (SiO2)
Quartz Grain / Sandstone Fragment
Silicon Dioxide (SiO2)
Calcite with Quartz coating
Calcium Carbonate (CaCO3) with Silicon Dioxide (SiO2)
Magnetite (likely with weathered Limonite/Hematite)
Magnetite (Fe3O4) with iron oxide weathering
Clear Quartz
Silicon Dioxide (SiO2)
Chert (Flint nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Sandstone
Clastic sedimentary rock (Quartz arenite)
Limonite (Iron Ore)
Limonite (Hydrated Iron Oxide, FeO(OH)·nH2O)
Sandstone
Sedimentary Rock (Quartz arenite / Lithic sandstone)
Bauxite
Bauxite (Al(OH)3, γ-AlO(OH), and α-AlO(OH))
Microcrystalline Quartz (Chert/Agate)
Silicon Dioxide (SiO2)
Fluorite
Calcium Fluoride (CaF2)
Hematite
Iron(III) oxide (Fe2O3)
Tree Agate
Dendritic Chalcedony (SiO2)
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Sandstone
Quartz Arenite / Clastic Sedimentary Rock
Hematite (Iron Ore)
Iron(III) oxide (Fe2O3)
Botryoidal Quartz
Silicon Dioxide (SiO2)
Tumbled White Quartz
Silicon Dioxide (SiO2)
Druzy Quartz on Ironstone
Silicon Dioxide (SiO2) on Limonitic Ironstone
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Celestite
Celestine (SrSO4)
Quartz pebble
Silicon dioxide (SiO2)
Fossiliferous Limestone
Biogenic Sedimentary Rock / CaCO3 with fossil fragments
Sandstone (Banded)
Arenite (primarily SiO2)
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite (specifically Iron-stained Quartz Sandstone)
Bauxite (Pisolitic Bauxite)
Bauxite (mixture of Hydrous Aluminum Oxides)
Sandstone
Arenite (SiO2 predominantly)
Bauxite
Alumina-rich rock (consisting of Gibbsite, Boehmite, and Diaspore)
Sandstone (Tafoni Weathered)
Arenite (part of the Sandstone family)
Fossiliferous Limestone with Crinoid Stem
Bioclastic Limestone (CaCO3)
Sandstone
Arenite (SiO2 primarily)
Sandstone
Arenite (Silicon Dioxide, SiO2 based)
Sandstone
Arenite (SiO2 based)
Sandstone
Arenite
Red Sandstone
Arenite (Fe2O3 rich)
Calcite
Calcium Carbonate (CaCO3)
Sandstone
Sedimentary Rock (Quartzose Sandstone)