Rough Quartz (Alluvial Pebbles)
Silicon Dioxide (SiO2)
Category
Browse man made material (anthropogenic 'mineraloid') specimens identified by the Rock Identifier community.
Rough Quartz (Alluvial Pebbles)
Silicon Dioxide (SiO2)
Gneiss
Gneiss (a rock type, not a specific mineral with a formula)
Quartz (Milky Quartz)
Quartz (SiO2 - Silicon Dioxide)
Quartz (River Pebble)
Quartz (SiO₂ - Silicon Dioxide)
Pearl
Aragonite (CaCO3 with conchiolin)
Pearl (nacre)
Calcium Carbonate (mostly CaCO3 as Aragonite) and Conchiolin
Limonite and Goethite (Ironstone)
Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)
Prase Quartz on Feldspar
Quartz (Silicon Dioxide, SiO2) with Hedenbergite inclusions on Potassium Feldspar (KAlSi3O8)
Quartz
Quartz (SiO₂)
Coquina
Bioclastic Limestone (composed primarily of CaCO3)
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Diamond (Cluster Ring)
Carbon (C)
Granite (Pegmatitic)
Phaneritic Felsic Igneous Rock
Diamond in Kimberlite
Diamond (C in Kimberlite Matrix)
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
Rough Diamond
Diamond (pure Carbon, C)
Red Coral
Corallium rubrum (for precious red coral), although other species like Corallium japonicum and Paracorallium are also used.
Pearl (with Peridot)
Calcium carbonate (CaCO3) + Conchiolin; Peridot: Magnesium iron silicate (Mg, Fe)2SiO4
Schist
Schist (various mineral compositions)
Rough Diamond
Diamond (pure Carbon, C)
Chalk
Micrite (primarily Calcium Carbonate, CaCO3)
Pink Granite
Phaneritic Felsic Igneous Rock
Pearl
Aragonite (CaCO3) with Conchiolin
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
Quartz-veined Siltstone
Siltstone with Quartz (SiO2) veins
Turquoise
Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O
Gabbro
Gabbro (composed mainly of calcium-rich plagioclase feldspar and pyroxene)
Quartzite
Quartzite (SiO2)
Amber
Succinite (specifically Baltic Amber) - Formula: C10H16O (approximate)
Agate (or Banded Agate)
Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)
Fluorite (likely)
Calcium Fluoride (CaF2)
Granodiorite with Quartz Veining
Granodiorite (containing Plagioclase Feldspar, Quartz, and Biotite/Hornblende) with Quartz (SiO2) veins
Pearl (in a decorative hair comb setting)
Calcium carbonate (CaCO3) primarily as Aragonite, bonded with Conchiolin
Pearl (Imitation or Cultured)
Calcium Carbonate (Aragonite/Calcite) - CaCO3
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Pyrite
Iron Disulfide (FeS2)
Lazulite
Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2
Chalcedony (Banded/Mottled Variety)
Chalcedony (a cryptocrystalline variety of Quartz, SiO2)
Diamond (or Diamond Simulant)
Carbon (C)
Amber
Succinite
Amber
Succinite (fossilized tree resin)
Sandstone (likely Quartzose Sandstone)
Arenite (composed primarily of SiO2)