Granite
Phaneritic Igneous Rock (composed mostly of Quartz, Feldspar, and Mica)
Category
Browse industrial by product specimens identified by the Rock Identifier community.
Granite
Phaneritic Igneous Rock (composed mostly of Quartz, Feldspar, and Mica)
Vesicular Basalt
Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
Red Shale
Fissile Siliciclastic Sedimentary Rock
Iron Ore (Limonite and Hematite)
Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Pumice
Pumicite
Basalt
Basalt (composition predominately plagioclase feldspar and pyroxene)
Pumice
Pumice (Amorphous volcanic glass)
Chert (Tripolitic Chert / Flint Nodules)
Microcrystalline Quartz (SiO2)
Sapphire in a ring
Corundum (Al2O3)
Garnet Schist
Almandine-Mica Schist
Ironstone Concretion (Limonite/Goethite)
Ferruginous concretion (Fe2O3·nH2O)
Limestone (containing Fossil Mold)
Sedimentary Calcium Carbonate (CaCO3)
Quartzite (River Pebble)
Metamorphic Quartzite (SiO2)
Diamond (in jewelry setting)
Diamond (C - Pure Carbon)
Agate
Agatized Chalcedony (SiO2)
Diamond
Diamond (C)
Greenish Metamorphic Rock (likely containing epidote or chlorite)
Metamorphic rock, possibly epidosite or greenstone
Quartzite
Quartzite
Quartzite (River Pebble)
Metamorphosed Quartz Sandstone (SiO2)
Limestone Pebble
Limestone (Calcium Carbonate, CaCO3)
Quartz (Small Fragment)
Silicon Dioxide (SiO2)
Chalcedony
Cryptocrystalline Quartz (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz with Iron Inclusions
Quartz (Silicon Dioxide, SiO2)
Quartzite Pebble
Quartzite (primarily SiO2)
Quartz Druzy (Geode Fragment)
Silicon Dioxide (SiO2)
Amethyst (Raw Quartz)
Amethyst (Silicon Dioxide with Iron impurities, SiO2)
Diamond
Diamond (pure Carbon, C)
Ruby
Corundum (Al2O3 with chromium impurities)
Quartz Pebble
Silicon Dioxide (SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Stilbite
Stilbite-Ca (NaCa4(Si27Al9)O72·28H2O)
Chalcedony (Common Opal variant)
Silicon dioxide (SiO2) with varying levels of hydration
Rough Quartz
Silicon Dioxide (SiO2)
Iron-stained Quartz (with Limonite/Hematite)
Silicon Dioxide (SiO2) with Iron Oxide inclusions (FeO(OH) or Fe2O3)
Piddock-bored Mudstone
Lutite (Siltstone or Mudstone) with Pholad borings
Black Tourmaline
Schorl (Sodium Iron Aluminum Borosilicate Hydroxide), NaFe3Al6(BO3)3Si6O18(OH)4
Quartzite Pebble
Quartzite (SiO2)
Garnet (Pyrope-Almandine series)
Garnet Group, (Mg,Fe)3Al2Si3O12
Black Tourmaline (Schorl)
Sodium Iron Aluminum Borosilicate (NaFe2+3Al6(Si6O18)(BO3)3(OH)3OH)
Olivine Peridotite
Peridotite (comprising Olivine (Mg,Fe)2SiO4 and Pyroxene)
Olivine (Peridotite)
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)