Diamond (or Lab-Grown Cubic Zirconia)
Carbon (C)
mineral
Category
Industrial Byproduct (Often Mistaken For Obsidian Or Mineral)
Browse industrial byproduct (often mistaken for obsidian or mineral) specimens identified by the Rock Identifier community.
Synthetic Resin (Artificial Specimen)
Polyurethane or Polyester Resin
mineraloid (man-made)
Garnet (Almandine)
Almandine, Fe3Al2(SiO4)3
metamorphic
Chert (variously Flint)
Chert (Microcrystalline or cryptocrystalline Quartz, SiO₂)
sedimentary
Piddock-bored Mudstone
Lutite (Siltstone or Mudstone) with Pholad borings
sedimentary
Agate
Chalcedony (cryptocrystalline quartz)
Mineral
Sand Grain (Silica/Quartz Grain)
Silicon Dioxide (SiO2)
sedimentary
Granitic Pegmatite
Granite (with coarse-grained Quartz, Feldspar, and Mica components)
igneous
Quartzite
Quartzite (primarily SiO2)
metamorphic
Pumice
Pumice (volcanic glass formed of highly vesicular rough textured rock)
igneous
Scoria (Red Lava Rock)
Scoria (Vesicular Basalt/Andesite)
igneous
Eclogite
Eclogite (composed primarily of Omphacite and Pyrope Garnet)
metamorphic
Grey Quartzite Pebble
Quartzite (primarily SiO2)
metamorphic
Olivine
Magnesium Iron Silicate ((Mg, Fe)₂SiO₄)
mineral
Quartzite (Beach Pebble)
Quartzite (primarily SiO2)
metamorphic
Botryoidal Chalcedony
Chalcedony (SiO2)
Mineral
Desert Rose (Baryte/Gypsum Rosette)
Baryte (BaSO4) or Gypsum (CaSO4·2H2O)
mineral
Chert (containing Flint nodules)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Pink Granite
Granite (Alkali-feldspar granite)
igneous
Man-made Jewelry Charm (Enameled Metal)
Not a natural mineral; composed of base metal alloy (likely zinc or brass) and epoxy resin/enamel.
Synthetic / Manufactured Artifact
Man-made Synthetic Material (Plastic/Composite)
Acrylonitrile Butadiene Styrene (ABS) or High-Impact Polystyrene (HIPS)
Non-geological / Synthetic
Basalt
Basalt (extrusive volcanic rock)
igneous
Chert (Jasper/Mudstone variant)
Silicon Dioxide (SiO2)
sedimentary
Serpentine
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3(Si, Al, Fe)2O5(OH)4
metamorphic
Cubic Zirconia (in Jewelry)
Zirconium Dioxide (ZrO2)
mineral
Schist
Mica Schist
metamorphic
Quartzite
Metamorphic Quartzite (predominantly SiO2)
metamorphic
Quartzite
Quartzite (chiefly SiO2)
metamorphic
Quartzite with Quartz Veining
Quartzite (consisting primarily of SiO2)
metamorphic
Fossilized Oyster Shell
Gryphaea or Crassostrea fossil (Calcium Carbonate, CaCO3)
sedimentary
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
metamorphic
Diamond (in Matrix)
Carbon (C)
mineral
Diamond (or Diamond Simulant/Cubic Zirconia)
Carbon (C) - if diamond, or Zirconium dioxide (ZrO2) - if Cubic Zirconia
mineral
Yellow Quartz (Citrine or Quartzite Pebble)
Silicon Dioxide (SiO2)
mineral
Silver (Native Element)
Ag (Argentum) - 90% Silver, 10% Copper alloy in specimen
mineral
Peridot in Basalt
Olivine ((Mg, Fe)2SiO4) in Basalt
mineral
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide inclusions
mineral
Granite
Granite (composed of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Quartzite
Quartzite (primarily SiO2)
metamorphic
Almandine Garnet
Almandine, Fe3Al2(SiO4)3
mineral