Magnetite (Iron Ore)
Magnetite (Fe3O4)
Category
Browse sedimentary (secondary classification for a weathered mineral specimen) specimens identified by the Rock Identifier community.
Magnetite (Iron Ore)
Magnetite (Fe3O4)
Carnelian Agate
Carnelian (Silicon Dioxide: SiO2) with iron oxide impurities
Chert (specifically Flint or Common Opal/Chalcedony mix)
Microcrystalline Quartz (SiO2)
Blue Sapphire
Corundum (Al2O3)
Peridot
Olivine (Mg, Fe)2SiO4
Chert (White/Light Tan)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Bornite
Bornite (Cu5FeS4)
Quartz (Double-Terminated)
Silicon Dioxide (SiO2)
Porphyritic Basalt (with Quartz or Calcite inclusion)
Porphyritic Basalt (Matrix: SiO2/MgO/FeO, Phenocryst: likely Quartz or Calcite)
Limestone with Weathering Rind
Calcium Carbonate (CaCO3) - Bioclastic or Micritic Limestone
Slate with Quartz
Low-grade Metamorphic Slate with SiO2 inclusions
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2) with impurities of Hematite or Goethite
Wishing Stone (Quartz-veined Siltstone or Graywacke)
Hydrothermal Quartz vein in matrix of SiO2 (Quartz) and Al2O3 (Clay minerals)
Gold Nugget
Native Gold (Au)
Native Gold Nugget
Native Gold (Au)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Druzy Quartz on Chert/Chalcedony
Silicon Dioxide (SiO2)
Chert / Flint (with Iron Staining)
Silicon Dioxide (SiO2)
Green Chalcedony (likely Chrysoprase or dyed Green Agate)
Silicon Dioxide (SiO2) with nickel impurities or chromium/dye
Picture Jasper
Silicon Dioxide (SiO2) with mineral inclusions
River Pebble (Brecciated Chert/Siltstone)
Silicon Dioxide (SiO2) with mineral inclusions
Lake Superior Agate
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Bull Quartz
Quartz (Silicon Dioxide - SiO2)
Agate
Chalcedony (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Banded Chert (with Quartz Vein)
Microcrystalline Silica (SiO2)
Jasper with Epidote Vein
Silicon Dioxide (SiO2) with Calcium Aluminum Iron Silicate (Ca2(Al,Fe)3(SiO4)3(OH))
Gold Nugget
Native Gold (Au)
Gold
Native Gold (Au)
N/A (Non-Geological Specimen)
Green Quartzite
Quartzite (primarily SiO2 with trace impurities)
Sedimentary Breccia
Breccia (Clastic Sedimentary Rock)
Quartzite
Quartzite (SiO2)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Honey Calcite
Calcium Carbonate (CaCO3)
Basalt with Scoria/Vesicular Texture
Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
Chert (specifically Flint or Dark Chert)
Chert (SiO2)
Gold
Native Gold (Au)
Basalt with Quartz/Calcite Veins
Basalt (Aphanitic Mafic Igneous Rock)
Chrysocolla
Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O
Chert (Jasper variety)
Cryptocrystalline quartz (SiO2)