Basalt
Basalt (Mafic volcanic rock)
Category
Browse not a rock or mineral specimens identified by the Rock Identifier community.
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (primarily composed of Plagioclase Feldspar and Pyroxene)
Sandstone
Arenite (composed primarily of SiO2)
Basalt with Quartz/Calcite matrix
Basalt (SiO2 with Ca/Mg/Fe silicates) on a Mineral Matrix
Sandstone
Clastic Sedimentary Rock (primarily Quartz, SiO2)
Schist
Mica Schist
Banded Gneiss
Gneiss (High-grade metamorphic rock)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Banded Agate (specifically Botswana Agate or Water-line Agate)
Chalcedony (cryptocrystalline variety of Quartz), SiO2
Quartz Pebble
Silicon Dioxide (SiO2)
Amethyst
Amethyst (Silicon Dioxide, SiO2 with Iron impurities)
Milky Quartz
Silicon Dioxide (SiO2)
Okenite (in Zeolite matrix)
Okenite (CaSi2O5 · 2H2O)
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
Ferruginous Sandstone
Arenite with Iron-oxide cement (composed of Quartz and Limonite/Hematite)
Chrysocolla in Matrix
Hydrated copper phyllosilicate mineral (Cu,Al)2H2Si2O5(OH)4·nH2O
Basalt (with possible Olivine inclusions)
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Quartz Vein in River Siltstone
Crystalline Quartz (SiO2) in Siliclastic Matrix
Quartz with Limonite Staining
Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)
Wishing Stone (Gneiss or Basalt with Quartz Vein)
Gneiss or Metabasalt (with a Quartz or Calcite intrusion)
Pyrite in Shale
Iron Sulfide (FeS2) in Sedimentary Matrix
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Red Sandstone
Arenite (predominantly Quartz with Hematite cementation)
Sandstone
Arenite (SiO2 based with quartz grains)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Diorite (River Rock)
Intermediate plutonic igneous rock
Quartz (likely Clear Quartz or Rock Crystal)
Quartz (SiO2)
Sandstone (Micaceous Sandstone)
Arenite (SiO2 with KAl2(AlSi3O10)(OH)2 inclusions)
Malachite Coating on Host Rock
Malachite [Cu2CO3(OH)2]
Gneiss
Gneiss
Ironstone Concretion
Siderite or Ferruginous Concretion (FeCO3 or Iron Oxides)
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
Granite
Granite (Felsic Plutonic Rock)
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with iron oxide and other mineral impurities
Sandstone (Quartzose)
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Granite
Phaneritic Felsic Igneous Rock
Vesicular Basalt with Secondary Mineral Inclusions
Aphanitic Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Chalcedony on Matrix
Silicon Dioxide (SiO2)
Granodiorite Pebble
Granodiorite
Quartz / Common Opal Transition
Silicon Dioxide (SiO2)