Sandstone Concretion
Clastic Sedimentary Rock (primarily SiO2 with mineral cement)
sedimentary
Category
Man Made Object (Coin)
Browse man made object (coin) specimens identified by the Rock Identifier community.
Chert Concretion (with typical hematite/limonite staining)
Sedimentary Concretion (SiO2 with FeO(OH)⋅nH2O)
sedimentary
Opalite
Synthetic Opalite Glass (Silicon Dioxide)
mineraloid (man-made)
Orange Calcite
Calcium Carbonate (CaCO3)
mineral
Common Marble
Calcium Carbonate (CaCO3)
metamorphic
Green Glass (often marketed as 'Obsidian' or 'Green Quartz')
Amorphous Silica (SiO2) with copper or chromium additives
Mineraloid (Man-made)
Goldstone (Red)
Aventurine Glass (SiO2 + Cu)
Synthetic Glass (Often categorized as a simulated mineral)
Ferro-slag (Leland Blue/Slag Glass)
Anthropogenic Vitreous Silica (Industrial Slag)
igneous
Sea Glass (White/Clear)
Amorphous Silica (Alkali-Lime-Silica Glass), SiO2 + Na2O + CaO
Anthropogenic (Man-made product subject to geological processes)
Red Slag Glass
Amorphous Silica (Industrial byproduct with metallic oxide dopants)
Mineraloid / Industrial Byproduct
Aura Quartz
Titanium/Titanium-Gold treated Silicon Dioxide (SiO2)
mineral
Conglomerate
Conglomerate Rock (Paraconglomerate)
sedimentary
Green Aventurine
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Slag
Ferrous Slag (Amorphous calcium-magnesium-aluminum silicates)
igneous (artificial/anthropogenic)
Calcite
Calcium Carbonate (CaCO3)
mineral
Opalite
Synthetic Opalised Glass
Mineral (Synthetic / Man-made)
Carborundum (Silicon Carbide)
Silicon Carbide (SiC) / Moissanite (natural form)
mineral
Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)
Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)
mineraloid / industrial byproduct
Banded Calcite (often commercially sold as 'Mexican Onyx' or 'Honey Onyx')
Calcite (Calcium Carbonate, CaCO3)
sedimentary
Hematite
Iron(III) oxide (Fe2O3)
mineral
Blue Crackle Quartz (Dyed Quarzite)
Silicon Dioxide (SiO2) with artificial dye
Metamorphic (modified)
Diamond
Native Carbon (C)
mineral
Dyed Aura Quartz
Silicon Dioxide (SiO2) with metallic coating
mineral
Porcelain Tile (Sandstone-look)
Man-made Ceramic (resembling Quartz-rich Sandstone)
sedimentary (imitation)
Blue Goldstone
Synthetic Avanturine Glass (or Aventurine Glass)
Synthetic Glass
Pink Cubic Zirconia (CZ)
Zirconium Dioxide (ZrO2)
mineral (synthetic)
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (Calcium Carbonate, CaCO3)
sedimentary
Granodiorite
Granodiorite
igneous
Amazonite
KAlSi3O8 (Potassium Aluminum Silicate)
mineral
Orange Calcite (Polished Sphere)
Calcium Carbonate (CaCO3)
mineral
Cullet (Slag Glass)
Amorphous Silica (Industrial byproduct)
mineraloid
Green Aventurine
Quartz (SiO2) with Fuchsite inclusions
Mineral
Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)
Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)
sedimentary
Aventurine
Quartz containing inclusions of Fuchsite (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
metamorphic
Ferro-silicate Slag
Industrial Vitrified Slag (High-silica amorphous glass)
Mineral byproduct (Anthropogenic)
Opalite (Man-made Glass)
Fused glass (typically made of dolomite and metal opacifiers)
Man-made Material / Glass
N/A (Non-Geological Object)
N/A
Pet Rock (Man-made Quartzite or Granite Cobble)
Silicon dioxide (SiO2) mixture; commonly composed of Quartz, Feldspar, and Mica
igneous or metamorphic (base stone); anthropogenic (decoration)
Sandstone (with man-made markings)
Arenite (composed primarily of Quartz, SiO2)
sedimentary
Libyan Desert Glass
Impact-melt silica glass (SiO2 + traces of Al, Fe, Ti)
mineral (Tektite/Impactite)
Dyed Crackle Quartz
Silicon Dioxide (SiO2) with synthetic dye
mineral
Man-made Jewelry (Metal and Glass/Plastic)
Synthetic Alloy and Amorphous Solid (SiO2/Polymer)
not a rock