Ruby
Corundum (Al2O3 with chromium impurities)
Category
Browse industrial byproduct specimens identified by the Rock Identifier community.
Ruby
Corundum (Al2O3 with chromium impurities)
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Quartz (Citrine or Iron-Stained variety)
Silicon Dioxide (SiO2)
Greenish Metamorphic Rock (likely containing epidote or chlorite)
Metamorphic rock, possibly epidosite or greenstone
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 cement)
Banded Agate
Chalcedony / Silicon Dioxide (SiO2)
Quartz with Iron Staining
Silicon Dioxide (SiO2)
Limonite (Iron Ore)
Limonite (̑FeO(OH)·nH₂O)
Chert (specifically Jasper/Flint)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartzite River Rock
Quartzite (SiO2)
Quartzite
Quartzite (SiO2)
Clear Quartz (Druzy)
Crystalline Silicon Dioxide (SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Quartz (Milky or Cloudy variety)
Quartz (Silicon Dioxide, SiO2)
Arfvedsonite (often mistakenly sold as Astrophyllite)
Arfvedsonite [Na3(Fe2+)4Fe3+Si8O22(OH)2]
Gold Ore in Quartz
Auriferous Quartz (Au + SiO2)
Graphite Schist
C (Carbonaceous Schist)
Green Calcite
Calcium Carbonate (CaCO3)
Quartzite
Quartzite (Primary mineral: Silicon Dioxide, SiO2)
Ironstone Concretion (Limonite/Goethite)
Ferruginous concretion (Fe2O3·nH2O)
Quartz (Small Fragment)
Silicon Dioxide (SiO2)
Quartz Druze on Matrix
Silicon Dioxide (SiO2)
Marble
Recrystallized Calcite Rock (CaCO3)
Grey Agate (Tumbled)
Silicon Dioxide (SiO2)
Quartz Pebble (Chalcedony/Agate)
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Satin Spar (often sold as Selenite)
Gypsum (CaSO4·2H2O)
Quartz Pebble
Silicon Dioxide (SiO2)
Smoky Quartz (Ferruginous Quartz)
Quartz (Silicon Dioxide, SiO2)
Iron-stained Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Orange Calcite (often commercially sold as Honey Calcite or Aragonite)
Calcium Carbonate (CaCO3)
Sapphire in a ring
Corundum (Al2O3)
Diamond (in a metal ring setting)
Diamond (Pure Carbon, C)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Quartz Druzy (Geode Fragment)
Silicon Dioxide (SiO2)
Quartz (Milky Quartz / Greenish Quartz)
SiO2 (Silicon Dioxide)
Agate (specifically Oco or Banded Agate)
Agate (a variety of Chalcedony), SiO2 (Silicon Dioxide)
Diamond
C (Carbon)
Pegmatitic Granite
Granite with Orthoclase Feldspar and Quartz (SiO2, KAlSi3O8)