Sandstone (Limonitic/Iron-stained)
Sandstone (containing Quartz, SiO2, and Limonite, FeO(OH)·nH2O)
Category
Browse mineral description (anthropogenic material) specimens identified by the Rock Identifier community.
Sandstone (Limonitic/Iron-stained)
Sandstone (containing Quartz, SiO2, and Limonite, FeO(OH)·nH2O)
Red Sandstone
Arenite (Ferruginous Sandstone)
Sandstone (Ferruginous)
Arenite with Iron Oxide cement
Sandstone (Quartzose Sandstone)
Clastic sedimentary rock (SiO2 major component)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 cementation)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Fluorite
Calcium fluoride (CaF2)
Limonite Concretion (Goonie or Rattlestone)
Limonite (FeO(OH)·nH2O)
Chakra Tumbled Stone Set
Various (including Amethyst [SiO2], Sodalite [Na8(Al6Si6O24)Cl2], Green Aventurine [SiO2], Red Jasper [SiO2], etc.)
Sandstone
Arenite
Polished black obsidian pyramid/block
Obsidian — natural volcanic glass, chiefly rhyolitic silica (approximately 70–75% SiO₂)
Gravel and Pavement Aggregates
Unconsolidated rock fragments / detrital sediments
Sandstone
Sedimentary Clastic Rock (Quartz Arenite)
Polychrome Jasper (Desert Jasper)
Silicon Dioxide (SiO2) with iron and mineral inclusions
Limestone
Calcium Carbonate (CaCO3)
Polished green aventurine
Quartzite or quartz-rich rock containing fuchsite mica; mainly SiO₂
Petrified Wood
Silicified wood (primarily SiO2)
Petrified Wood
Silicon Dioxide (SiO2) - Calcified / Silicified Wood
Petrified Wood
Silicified Wood (primarily Chalcedony or Quartz, SiO2)
Conglomerate
Conglomerate (clastic sedimentary rock)
Chert Nodule
Chert (Microcrystalline Silicon Dioxide, SiO2)
Sandstone
Arenite (composed primarily of SiO2)
White Quartz
Quartz (Silicon Dioxide, SiO2)
Diamond
Diamond (C)
Quartzite or Quartz Vein Material
SiO2
Greenstone
Metamorphic mafic rock (greenschist facies)
Nuummite
Orthoamphibole (Gedrite-Anthophyllite series)
Iron-stained quartz-rich rock, possibly goethite-bearing quartz
Quartz (SiO₂) with iron oxides/hydroxides, likely goethite or limonite
Limonite/goethite-rich ironstone (probable)
Limonite, chiefly hydrated iron oxides; commonly goethite, α-FeO(OH), with possible quartz or host-rock inclusions
Sandstone (Water-worn Cobble)
Arenite (variable composition, primarily SiO2)
Shark Tooth Fossil
Carcharocles megalodon or similar fossilized shark tooth
Brachiopod Fossil
Phylum Brachiopoda
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone (Pebble)
Sandstone (SiO2 dominated with minor feldspar/clay)
Sandstone (Weathered)
Arenite (typically SiO2 as quartz grains)
Sandstone (Weathered Pebble)
Arenite (SiO2 primarily)
Sandstone
Arenite
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Bauxite
Bauxite (Al(OH)3, γ-AlO(OH), and α-AlO(OH))
Quartz Vein in Sandstone
Hydrothermal Quartz (SiO2) in Arenite