Iron Ore (Limonite and Hematite)
Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Category
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Iron Ore (Limonite and Hematite)
Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)
Red Sandstone
Sandstone (principally Quartz with Iron Oxide coating)
Lapis Lazuli (Tumbled Specimen)
Lapis Lazuli (Aggregate rock containing Lazurite: (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2)
Gold Ore in Quartz
Native Gold (Au) in Quartz (SiO2)
Orpiment
Orpiment (As2S3)
Quartz (Variety of Rough Mineral Specimens)
Silicon Dioxide (SiO2)
Schist
Mica Schist
Shattuckite (Blue Quartz/Jasper Matrix)
Shattuckite (Copper Silicate Hydroxide - Cu5(SiO3)4(OH)2)
Gold
Native Gold (Au)
Sandstone
Arenite
Quartz with Mica inclusions (Pegmatite)
Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions
Granite
Phaneritic Acidic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Pyrite (on host rock)
Iron Sulfide (FeS2)
Sandstone (with Concretion)
Arenite / Quartzose Sandstone
Milk Quartz (White Quartz)
Silicon Dioxide (SiO2)
Fluorite (Rainbow Fluorite)
Calcium Fluoride (CaF2)
Green Fluorite
Calcium Fluoride (CaF2)
Banded Quartz
Silicon Dioxide (SiO2)
Green Fluorite
Calcium Fluoride (CaF2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Green Fluorite
Calcium Fluoride (CaF2)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Clear Quartz
Silicon Dioxide (SiO2)
Malachite Coating on Host Rock
Malachite [Cu2CO3(OH)2]
Chrysocolla in Matrix
Hydrated copper silicate - (Cu,Al)2H2Si2O5(OH)4·nH2O
Aventurine (likely Green Aventurine)
Silicon Dioxide (SiO2) with mineral inclusions
Sandstone (River Rock)
Arenite (composed primarily of SiO2)
Note: Item is not a geological specimen
n/a
Biotite (Mica)
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
Sandstone (with potential mineral inclusions)
Clastic sedimentary rock (primarily Quartz, SiO2)
Bronzite
MgSiO3 (Enstatite with 10-30% FeSiO3 in solid solution)
Banded Iron Formation (BIF) / Iron Ore
Banded Iron Formation (composed primarily of Hematite (Fe2O3) and Magnetite (Fe3O4) with Quartz/Chert)
Gneiss
Gneiss
Gneiss (specifically Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Biotite/Amphibole)
Coarse-grained Granite
Granitoid (KAlSi3O8 + SiO2 + NaAlSi3O8)
Granite
Granite (Felsic Plutonic Rock)
Gneiss
Gneiss (High-grade metamorphic rock composed primarily of Quartz, Feldspar, and various Micas)
Gold-bearing Quartz
Lode Gold in Silicon Dioxide (SiO2)
Aquamarine
Beryl (Be3Al2Si6O18 with trace Fe2+)
Limonite (Iron Ore)
Limonite; FeO(OH)·nH2O
Amber
Fossilized Resin (C10H16O)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Extrusive volcanic rock)