Greenstone
Metabasalt / Chlorite-Epidote Schist
Category
Browse sedimentary rock (possibly composed of various minerals) specimens identified by the Rock Identifier community.
Greenstone
Metabasalt / Chlorite-Epidote Schist
Schist (Kyanite Schist)
Kyanite-Mica Schist (primarily Al2SiO5, KAl2(AlSi3O10)(OH)2, and SiO2)
Magnetite / Iron Ore
Magnetite (Fe3O4)
Sandstone (specifically Red Sandstone)
Arenite (primarily Quartz, SiO2)
Quartz (Clear Quartz and Rose Quartz variants)
Silicon Dioxide (SiO2)
Herkimer Diamond (Quartz)
Silicon Dioxide (SiO2)
Lake Superior Agate
Banded Chalcedony (Silicon Dioxide / SiO2)
Native Gold
Gold (Au)
Sandstone (Cross-bedded Drill Core)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (Weathered Cobble)
Clastic Sedimentary Rock (primarily SiO2)
Basalt with Weathering Crust
Extrusive mafic volcanic rock
Quartz Conglomerate
Quartz Conglomerate (clastic sedimentary rock)
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (primarily SiO2)
Yellow Quartz (Citrine or Yellow Jasper)
Silicon Dioxide (SiO2)
Sandstone (Quartzose)
Arenite (SiO2 principal)
Quartz
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (variable SiO2 with Fe2O3 staining)
Sandstone Pebble
Arenite (primarily SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
Vesicular Basalt
Mafic Volcanic Rock (Basalt)
Graphite
Graphite (C)
Granite
Granite (High-silica plutonic rock)
Red Jasper
Jasper (Silicate mineral - SiO2)
Amethyst
SiO2 (Silicon Dioxide with iron impurities)
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Jasper
Silicon Dioxide (SiO2) - Jasper (Microcrystalline Quartz)
Ferruginous Siltstone or Mudstone
Ferruginous Siltstone / Goethitic Sandstone
Sunstone and Green Aventurine
Sunstone: (Ca,Na)[(Al,Si)2Si2O8] (Plagioclase Feldspar Group); Green Aventurine: SiO2 (Quartz)
Chert (Smooth River Pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide inclusions (Hematite/Goethite)
Agate
Silicon Dioxide (SiO2) - variety of Chalcedony
Sandstone
Arenite (primarily SiO2)
Sandstone (Quartz-rich)
Sandstone (SiO2 dominated)
Jasper
Silicon Dioxide (SiO2) - a variety of Chalcedony (Cryptocrystalline Quartz)
Granite
Intrusive Igneous Rock (composed primarily of Quartz: SiO2, Feldspar: KAlSi3O8, and Mica: KAl2(AlSi3O10)(OH)2)
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with iron oxide and other mineral impurities
Milky Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
Granite (weathered)
Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Slate
Slate (Regional metamorphic rock composed primarily of quartz, illite, and chlorite)
Pink Granite (Alkali Feldspar Granite)
Phaneritic Felsic Igneous Rock (composed primarily of KAlSi3O8, SiO2, and NaAlSi3O8)
Diorite
Phaneritic Intrusive Igneous Rock (composed of Plagioclase feldspar, Hornblende, and Biotite)
Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)