Quartz Pebble (Chalcedony/Agate variety)
Silicon Dioxide (SiO2)
Category
Browse industrial byproduct (anthropogenic rock) specimens identified by the Rock Identifier community.
Quartz Pebble (Chalcedony/Agate variety)
Silicon Dioxide (SiO2)
Blue Sapphire (likely costume glass imitation)
Corundum (Al2O3) with iron/titanium impurities
Quartz Geode (Water-worn)
Silicon Dioxide (SiO2)
Gold in Quartz
Hydrothermal Quartz with Native Gold (SiO2 with Au)
Marble
Recrystallized Calcite (CaCO3)
Sandstone
Arenite (SiO2, often with CaCO3 or Fe2O3 cement)
Mica in Quartz Host
Muscovite (KAl2(AlSi3O10)(OH)2) in Quartz (SiO2)
Porcelain Tile (Sandstone-look)
Man-made Ceramic (resembling Quartz-rich Sandstone)
Standing Liberty Quarter (Silver Specimen)
Native Silver alloy (Ag with Cu traces)
Opaline Glass (Opalite)
Synthetic Silicon Dioxide Glass
Smoky Quartz and Chalcedony Geode Fragment
Silicon Dioxide (SiO2)
Diamond in Kimberlite
Kimberlite Matrix with Carbon (Diamond)
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Sandstone
Arenite (SiO2 dominant)
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
Corundum (Pink Sapphire / Ruby)
Al2O3 (Aluminum Oxide)
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within metamorphic/igneous matrix
Bog Iron (Limonite)
Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)
Quartz pebble
Silicon Dioxide (SiO2)
Garnet (Almandine)
Almandine Fe3Al2(SiO4)3
Garnet in Matrix (Schist or Quartz)
Almandine Garnet, Fe3Al2(SiO4)3
Copper Ore (likely Malachite or Chrysocolla staining)
Copper Secondary Mineral (e.g., Cu2CO3(OH)2)
Quartzite
Quartzite
Quartzite
Quartzite (mostly SiO2)
Botryoidal Quartz
Silicon Dioxide (SiO2)
Granitic Gravel
Granite (Quartz, Feldspar, and Mica mixture)
Marble
Recrystallized Calcite / Metamorphosed Limestone (CaCO3)
Amber Calcite
Calcium Carbonate (CaCO3)
Quartz Pebble
Silicon Dioxide (SiO2)
Jasper
Jasper (Silica/Silicon Dioxide, SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Diamond (or Cubic Zirconia)
C (Carbon) or ZrO2 (Zirconium Dioxide)
Agate (Chert/Chalcedony)
Silicon Dioxide (SiO2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Silver (Jewelry Specimen)
Native Silver (Chemical Formula: Ag)
Wishing Rock (Quartz Vein in Host Rock)
Silicon dioxide (SiO2) vein in various host rocks
Talc (Soapstone variety)
Talc (Hydrated magnesium silicate) - Mg3Si4O10(OH)2
Quartz (Agate/Chalcedony variety)
Silicon Dioxide (SiO2)
Garnet Beads
Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)
Basalt
Extrusive mafic igneous rock
Dalmatian Jasper
Peralkaline Quartz-Feldspar Rock with Arfvedsonite
Basalt Cobble
Vesicular Basalt (Mafic Extrusive)