Chert (with Chalky Cortex)
Silicon Dioxide (SiO2)
sedimentary
Category
Not A Natural Rock (Man Made Composite)
Browse not a natural rock (man made composite) specimens identified by the Rock Identifier community.
Sandstone (Ferruginous)
Arenite (Fe-rich)
sedimentary
Basalt
Basalt
igneous
Basalt
Basalt (principally Plagioclase and Pyroxene)
igneous
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Chert (Nodule)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Serpentine Schist with Quartz Vein
Serpentine Schist (a type of Metamorphic rock). The white band is likely Quartz (SiO2).
Metamorphic
Basalt
Basalt (Mafic volcanic rock)
igneous
Synthetic Zinc/Polycarbonate Composite (Bey-specimen)
Zinc Alloy (Zamak 3) with Polycarbonate (C15H16O2)n Overlay
Anthropogenic Mineral Mimic
Basalt
Extrusive mafic igneous rock
igneous
Fairburn Agate / Agate-bearing Breccia
Cryptocrystalline Quartz (SiO2) within Jasper/Breccia matrix
sedimentary
Sandstone
Arenite (primarily SiO2 - Silicon Dioxide)
sedimentary
Gastly (Trick or Trade Halloween Series)
Cellulose-carbonaceous composite (Lignocellulose laminated with pigmentary polymers)
Mineral (Synthetic - Paper and Ink Polymorph)
Quartz (Float/Abraded)
Quartz (SiO₂)
Mineral
Hematite
Iron(III) oxide (Fe2O3)
mineral
Amygdaloidal Basalt
Amygdaloidal Basalt (with secondary mineral infilling)
igneous
Banded Agate (specifically Sardonyx)
Silicon Dioxide (SiO2) - variety of Chalcedony/Quartz
mineral
Iron Slag
Ferrous Slag (complex silicate and oxide byproduct)
industrial byproduct (anthropogenic)
Red Jasper
Jasper (Silicon Dioxide with iron oxide inclusions), SiO2
mineral
Native Copper
Native Copper (Cu)
mineral
Sandstone (Quartzose Sandstone Pebble)
Arenite (primarily SiO2)
sedimentary
Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily Quartz, SiO2)
sedimentary
Sandstone
Arenite
sedimentary
Sandstone (Quartz-rich)
Arenite (SiO2 based clastic rock)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Crushed Limestone
Calcium Carbonate (CaCO3)
sedimentary
Granodiorite (or Granite) Pebble
Phaneritic Felsic Igneous Pebble
igneous
Quartz
Quartz (SiO2 - Silicon Dioxide)
Mineral
Orthoclase Feldspar (or K-Feldspar)
Orthoclase (KAlSi3O8)
Mineral
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2)
sedimentary
Hematite
Iron(III) oxide (Fe2O3)
mineral
Snowflake Obsidian (or similar porphyritic volcanic rock)
Obsidian with Spherulites (if glassy), or Porphyritic Rhyolite/Andesite (if crystalline groundmass)
igneous
Healer's Gold (Pyrite and Magnetite in Schist)
Magnetite (Fe3O4) and Pyrite (FeS2) in Mica Schist
metamorphic
Quartz (likely milky quartz or a stained variety)
Silicon Dioxide (SiO₂)
Mineral
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
sedimentary