Gold Nugget
Native Gold (Au)
mineral
Category
Mineral Based Alloy (Anthropogenic)
Browse mineral based alloy (anthropogenic) specimens identified by the Rock Identifier community.
Learn about Mineral Based Alloy (Anthropogenic) in the encyclopedia
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Silver (Native Silver Mineral)
Ag (Native Silver), Alloyed 90% Ag / 10% Cu
mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Opal
Hydrated silica (SiO2·nH2O)
mineraloid
Conglomerate
Conglomerate (clastic sedimentary rock)
sedimentary
Conglomerate
Clastic Conglomerate (Lithic-rich)
sedimentary
Ruby in Fuchsite
Corundum (Al2O3) in Chrome-Mica (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Fossilized Coral (Petoskey Stone or similar)
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Fossiliferous Limestone (Coquina-like)
Biogenic Limestone
sedimentary
Conglomerate
Clastic Sedimentary (Conglomerate)
sedimentary
Iron Meteorite
Iron Meteorite (primarily Kamacite and Taenite, Fe-Ni alloys)
mineral
Iron Slag
Vitreous glassy waste (Fe-Si-Al-Ca compounds)
Mineral byproduct (anthropogenic / techno-fossil)
Opalite
Synthetic Opalised Glass
Mineral (Synthetic / Man-made)
Polygenetic Conglomerate (Puddingstone)
Conglomerate (SiO2 matrix with mixed clasts)
sedimentary
Quartz Vein in Sandstone
Sandstone with Hydrothermal Quartz (SiO2)
sedimentary
Anthracite
Anthracite (highest-grade coal)
metamorphic
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Sandstone (specifically Double Arch in Arches National Park)
Entrada Sandstone
sedimentary
Fossilized Coral (Petoskey Stone or similar Favosites)
Hexagonaria percarinata / Favosites (Silurian-Devonian Coral)
sedimentary
River Stone (River Pebble)
Stream-rounded clast (likely Quartzite or Siltstone)
sedimentary
Conglomerate
Clastic sedimentary rock (Conglomerate)
sedimentary
Limonite Stained Basalt
Hydrated Iron Oxide on Mafic Volcanic Rock (FeO(OH)·nH2O)
igneous
Quartzite River Rock
Quartzite (SiO2 based metamorphic rock)
metamorphic
Anthracite Coal
Anthracite (Carbon-based metamorphic rock)
metamorphic
Bituminous Coal
Organic Sedimentary Rock (Carbon-based)
sedimentary
Slate
Phyllo-silicate based metamorphic rock
metamorphic
Dragon's Breath (Mexican Opal Glass)
Artisan Foil Glass (SiO2 based)
mineraloid
Bituminous Coal
Organic Sedimentary Rock (Carbon-based)
sedimentary
Pyrite
Iron Pyrite (FeS2)
Mineral
Jasper (specifically Green Jasper/Chert)
Jasper (Silicon Dioxide, SiO2)
sedimentary
Quartz
Silicon Dioxide (SiO₂)
Mineral
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Laterite
Lateritic Soil/Rock (rich in Fe2O3 and Al2O3)
sedimentary
Sandstone
Arenite (SiO2 based with primary clasts 0.0625 to 2 mm)
sedimentary
Opalite
Synthetic Glass (typically Silica/Magnesium based with metal additives)
mineral
Bumble Bee Jasper
Volcanic Tuff (mixture of SiO2, CaCo3, S, and As2S3)
igneous
Dalmatian Jasper
Peralkaline Quartz-Feldspar Igneous Rock
igneous
Diamond (as set in a metal alloy ring)
Diamond (Pure Carbon, C)
mineral
Silver (Native Silver/Alloy Specimen)
Ag (Native Silver element), specifically a 90% Ag / 10% Cu alloy
mineral
Iron Meteorite (Fragment)
Siderite (Iron-Nickel alloy: Kamacite and Taenite)
igneous
Iron Meteorite
Iron-nickel alloy (primarily kamacite and taenite)
Meteorite (extraterrestrial material)
Iron Meteorite
Iron-nickel alloy (e.g., Kamacite, Taenite)
Meteorite (extraterrestrial material)