Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
Category
Browse organic materia (not a rock or mineral) specimens identified by the Rock Identifier community.
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
Sandstone
Arenite (primarily SiO2 with various cementing agents)
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)
Howlite and Purple Amethyst Druzy
Calcium Borosilicate Hydroxide (Howlite) and Silicon Dioxide (Quartz/Amethyst)
Banded Gneiss
Gneiss (High-grade Metamorphic Rock)
Granite
Phaneritic Igneous Rock (Granite)
Garnetiferous Quartzite (Garnet Gneiss Pebble)
Garnet-bearing Quartzite or Quartz-Feldspar Gneiss
Granite Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Diabase (Dolerite) Cobble
Diabase / Dolerite
Sandstone (Greywacke)
Arenite / Clastic Sedimentary Rock
Sandstone
Arenite
Quartz Geode
Silicon Dioxide (SiO2) within a secondary sedimentary structure
Quartz Vein / Milky Quartz
Silicon Dioxide (SiO2)
Schist (Garnet-Mica Schist)
Garnet-Mica Schist
Quartz Geode (partially formed)
Silicon Dioxide (SiO2)
Quartz Druze on Matrix
Silicon Dioxide (SiO2)
Lazulite
Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Sandstone (Ferruginous)
Sandstone (primarily SiO2 with Fe2O3 cement)
Gneiss (with Quartzite and Mica)
Gneiss
Granite
Phaneritic Felsic Igneous Rock (composed of SiO2, KAlSi3O8, NaAlSi3O8)
Schist
Schist (Crystalline metamorphic rock)
Greenstone
Metabasalt / Greenschist facies rock
Granite
Granite (Phaneritic igneous rock)
Tree Agate
Silicon Dioxide (SiO2) - Dendritic Agate/Chalcedony
River Rocks (Basalt and Sedimentary Stones)
Mafic Igneous Rock (Basalt) and Clastic Sedimentary Rock
Ferruginous Siltstone or Mudstone
Ferruginous Siltstone / Goethitic Sandstone
Quartz Geode
Silicon Dioxide (SiO2)
Blue Kyanite
Kyanite (Al2SiO5)
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
Chert (varietal: Jasper or Ironstone nodule)
Microcrystalline Quartz (SiO2) with iron oxides
Fancy Jasper (Agate/Chert mix)
Silicon Dioxide (SiO2) with impurities
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Gneiss
Gneiss
Gneiss
Gneiss (High-grade regional metamorphic rock)
Limestone
Calcium Carbonate (CaCO3)
General Rock and Mineral Collection (Center: Angelite / Blue Anhydrite)
Anhydrite (Calcium Sulfate, CaSO4)
Banded Agate (specifically Lake Superior Agate)
Silicon dioxide (SiO2) - Cryptocrystalline Chalcedony
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Nuummite
Nuummite (ortho-amphibole rock)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)