Sandstone (with potential iron mineralization)
Arenite
Category
Browse mineral (tectosilicate) specimens identified by the Rock Identifier community.
Sandstone (with potential iron mineralization)
Arenite
Limestone with Secondary Mineralization
Calcium Carbonate (CaCO3)
Granite
Phaneritic plutonic igneous rock (SiO2 range 65-75%)
Jadeite
NaAlSi2O6; Jadeite silicate mineral
Malachite
Copper(II) carbonate hydroxide [Cu2CO3(OH)2]
Serpentinite
Serpentinite
Gneiss (specifically a Banded Gneiss pebble)
Gneiss (High-grade Regional Metamorphic Rock)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Apatite
Apatite Group (e.g., Fluorapatite Ca5(PO4)3F, Chlorapatite Ca5(PO4)3Cl, Hydroxylapatite Ca5(PO4)3(OH))
Blue Apatite
Apatite - Ca5(PO4)3(F,Cl,OH)
Prehnite
Ca2Al2Si3O10(OH)2
Citrine Quartz
Silicon Dioxide (SiO2)
Emerald in Matrix
Beryl (Be3Al2Si6O18)
Geode (Unopened)
Silicon dioxide with various inclusions (SiO2)
Lake Superior Agate
Agate (Cryptocrystalline variety of Quartz, SiO2)
Precious Opal in Matrix
Hydrated Silica (SiO2·nH2O)
Peridot
Olivine (Mg, Fe)2SiO4
Amazonite
Microcline (KAlSi3O8) with lead impurities
Citrine
Crystalline Quartz (SiO2) with iron impurities
Emerald
Beryl (Be3Al2(SiO3)6) with chromium/vanadium impurities
Barite Rose on Marcasite
Barium Sulfate (BaSO4) on Iron Sulfide (FeS2)
Red Sandstone
Ferruginous Sandstone (SiO2 dominated with Fe2O3 cement)
Limonite with Iron Inclusions
Limonite (Hydrated Iron Oxide, FeO(OH)·nH2O)
Olivine (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4
Vesicular Basalt with Secondary Mineral Infill
Mafic Volcanic Rock (Basalt)
Potash (Sylvite/Potassium Feldspar)
Potassium chloride (KCl) or Orthoclase (KAlSi3O8)
Note on Image Identification: Textile
N/A (Anthropogenic material)
Brachiopod Fossil
Phylum Brachiopoda (likely Order Rhynchonellida or Spiriferida)
Arsenopyrite with Schist Matrix
Arsenopyrite (FeAsS)
Gneiss
Gneiss (Metamorphic high-grade)
Vanadinite
Vanadinite (Pb5(VO4)3Cl)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Gneiss
Gneiss
Basalt
Basalt
N/A - Non-Geological Item
Milky Quartz
Crystalline Silicon Dioxide (SiO2)
Milky Quartz with Country Rock contact
Silicon Dioxide (SiO2) in contact with Metamorphic/Igneous rock
Turquenite (Dyed Howlite)
Dyed Ca2B5SiO9(OH)5 (Calcium Borosilicate Hydroxide)
Tiger's Eye (Brown/Dark variety)
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Selenite / Gypsum
Gypsum (CaSO4·2H2O)
Prehnite
Prehnite, Ca2Al(AlSi3O10)(OH)2