Magnetite (Lodestone variety)
Magnetite (Iron(II,III) oxide, Fe3O4)
mineral
Category
Industrial By Product
Browse industrial by product specimens identified by the Rock Identifier community.
Aquamarine on Feldspar Matrix
Beryl (Be3Al2Si6O18) with Potassium Feldspar (KAlSi3O8)
mineral
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Tiffany Stone
Bertrandite Fluorite (CaF2 + Be4Si2O7(OH)2)
metamorphic
Peridot
Olivine ((Mg,Fe)2SiO4)
Mineral
Agate (specifically a Blue Agate Geode Slice)
Chalcedony (cryptocrystalline variety of Quartz); SiO2
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Fluorite (often called Rainbow Fluorite or Purple-Green Fluorite)
Calcium Fluoride (CaF2)
mineral
Anthracite Coal
Anthracite (Carbon-rich Sedimentary-to-Metamorphic Rock)
metamorphic
Basalt with Magnetite
Crystalline Basalt (Primarily Plagioclase and Pyroxene) with Magnetite (Fe3O4)
igneous
Magnetite / Iron Ore
Magnetite (Fe3O4)
mineral
Diamond
Native Carbon (C)
mineral
Granitic Pegmatite
Granitic Pegmatite (principally Quartz, Feldspar, and Mica)
igneous
Jasper (Red Jasper)
Silicon Dioxide (SiO₂)
sedimentary
Anthracite Coal
Anthracite
metamorphic
Pyrite
Iron Sulfide (FeS2)
mineral
Milky Quartz
Quartz (SiO2) with iron staining
mineral
Chert (specifically tan/pink variety)
Silicon Dioxide (SiO2)
sedimentary
Barite Rose on Marcasite
Barium Sulfate (BaSO4) on Iron Sulfide (FeS2)
mineral
Blue Calcite
Calcium Carbonate (CaCO3)
mineral
Honey Calcite
Calcium Carbonate (CaCO3)
mineral
Epidote in Matrix
Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Quartz Druzy on Matrix (likely Agate or Jasper)
Silicon Dioxide (SiO2) with various mineral inclusions
mineral
Milky Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
mineral
Satin Spar (Selenite)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
mineral
Garnet (specifically Almandine or Pyrope)
Almandine: Fe3Al2(SiO4)3 or Pyrope: Mg3Al2(SiO4)3
mineral
Jasper and Quartz River Pebble
Silicon Dioxide (SiO2) with impurities
sedimentary
Garnet
Garnet Group (Silicate mineral); general formula X3Y2(SiO4)3
mineral
Black Sapphire
Corundum (Al2O3 with inclusions of hematite or ilmenite)
mineral
Satin Spar (often marketed as Selenite)
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
mineral
Rose Quartz
SiO2 (Silicon Dioxide)
mineral
Yellow Quartz (Citrine or Yellow Chalcedony)
Silicon Dioxide (SiO2)
mineral
Quartzite (Beach Pebble)
Quartzite (SiO2)
metamorphic
Milky Quartz (Quartz Vein)
Silicon Dioxide (SiO2)
mineral
Blue Dumortierite Quartz
AlAl6BSi3O18 (Dumortierite) within SiO2 (Quartz)
mineral
Chert (White Chert / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Quartzite River Stone
Metamorphic Quartzite (primarily SiO2)
metamorphic
Chert (Green Chert/Jasper)
Chert (primarily Microcrystalline Quartz, SiO2)
sedimentary
Pink Quartz / Rose Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone Beach Pebble
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide coating)
sedimentary
Pegmatite (White Granite variant)
Pegmatitic Granite (Quartz and Feldspar rich)
igneous
Ironstone (likely Ferruginous Siltstone/Sandstone)
Ferruginous sedimentary rock (FeOx-rich clastic)
sedimentary