Carnelian
Chalcedony (cryptocrystalline quartz), SiO2
Mineral
Category
Man Made Composite (Lithified Equivalent Of Sedimentary)
Browse man made composite (lithified equivalent of sedimentary) specimens identified by the Rock Identifier community.
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Sea Glass (Teal/Turquoise)
Amorphous Silica (SiO2) with trace metal oxides
Anthropogenic (Man-made material processed by nature)
Sea Glass (Turquoise/Aqua)
Amorphous Silica (SiO2) with transition metal dopants
Anthropogenic (Man-made material processed by nature)
Weathered pegmatite or feldspar-rich granite fragment
Granitic pegmatite, composed mainly of potassium feldspar and quartz, with minor mica; exact identification is uncertain from the photograph
igneous
Amber (Copal)
Organic gemstone, fossilized tree resin (often immature amber or copal)
Mineral
Sea Glass (Frosted Glass)
Amorphous Silica (SiO2) with various metal oxide impurities
Man-made material (Anthro-lithic product)
Metal Alloy (Jewelry)
Not a naturally occurring rock or mineral; likely a metal alloy for jewelry. Possible compositions include sterling silver (92.5% silver, 7.5% copper), or other silver/gold alloys.
Man-made Material (jewelry, metal alloy)
United States Quarter Dollar
Cupronickel Clad Alloy (75% Copper, 25% Nickel over a 100% Copper core)
Metal / Man-made mineral-like object
Green Glass Cullet / Recycled Glass
Amorphous Silicon Dioxide (SiO2) with various metal oxides
Man-made Glass (Not a natural rock or mineral)
Quartz
Silicon Dioxide (SiO₂)
Mineral
Fordite
Anthropogenic paint-rock
mineraloid (human-made geological specimen)
Cullet Glass (Industrial Slag Glass)
Amorphous Silica (SiO2) with metallic oxide impurities
Man-made byproduct (often mistaken for Obsidian or Emerald)
Muscovite Mica
Muscovite (Potassium Aluminum Silicate Hydroxide Fluoride), KAl2(AlSi3O10)(OH,F)2
mineral
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Metallic Ornament / Jewelry
N/A - This is an artificial object, not a geological specimen.
This appears to be a man-made metallic object, likely jewelry, not a natural rock, mineral, or geological specimen.
Porphyritic Rhyolite
Rhyolite (Porphyry)
igneous
Gabbro
Gabbro (Coarse-grained mafic intrusive igneous rock)
igneous
Vesicular Rhyolite
Rhyolite (High-silica volcanic rock)
igneous
Sandstone (with potential mineral inclusions)
Clastic sedimentary rock (primarily Quartz, SiO2)
sedimentary
Sandstone Pebble
Arenite (primarily SiO2)
sedimentary
Blue quartzite or blue aventurine glass-like aggregate
Quartzite, predominantly SiO₂ (identification uncertain from image)
metamorphic
Sandstone (Ferruginous)
Arenite (Fe2O3 stained)
sedimentary
Basalt
Basalt
igneous
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Sandstone
Arenite (SiO2 based)
sedimentary
Granite
Granite (plutonic igneous rock)
igneous
Sandstone (Quartzose Sandstone)
Arenite (primarily SiO2)
sedimentary
Sandstone
Arenite (Clastic Sedimentary Rock)
sedimentary
Sandstone (likely Arkosic or Lithic Sandstone)
Sandstone (SiO2 predominant)
sedimentary
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Sandstone (Ferruginous)
Arenite (with Iron Oxide)
sedimentary
Sandstone (Ferruginous)
Arenite (Fe-rich)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Coarse Sandstone
Arenite (SiO2 based)
sedimentary
Sandstone
Arenite (Sedimentary rock composed of sand-sized grains)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Sandstone
Arenite
sedimentary
Sandstone
Arenite (Sedimentary rock)
sedimentary
Sandstone
Arenite (SiO2 primarily)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Sandstone
Arenite (SiO2 based with mineral cement)
sedimentary
Sandstone
Arenite (primarily SiO2 with various cementing agents)
sedimentary