Weathered iron-rich rock, possibly jasper or ironstone
Likely limonite/goethite-bearing siliceous rock; exact identification requires hardness and streak tests
Category
Browse man made rock (sedimentary analogue) specimens identified by the Rock Identifier community.
Weathered iron-rich rock, possibly jasper or ironstone
Likely limonite/goethite-bearing siliceous rock; exact identification requires hardness and streak tests
Chert
Microcrystalline Quartz (SiO2)
Chert (Grey-Green Flint)
Microcrystalline silicon dioxide (SiO2)
Pumice
Pumice (Vitreous volcanic rock)
Breccia
Breccia
Iron-stained quartz-rich rock, possibly jasper or chert
Microcrystalline quartz (SiO₂) with iron oxides/hydroxides
Geode (Unopened)
Quartz Geode (SiO2) / Chalcedony Concretion
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
Chert (Quartz Variety)
Chert (Silicon Dioxide, SiO2)
Sandstone (Red/Brown Variety)
Arenite (composed primarily of SiO2 with Fe2O3 iron oxide inclusions)
Flint or chert, possibly a knapped stone tool
Microcrystalline quartz (SiO₂), commonly chalcedony with possible carbonaceous impurities
Diamond Druzy (Crystalline Diamond)
Carbon (C)
Man-made Jewelry Charm (Enameled Metal)
Not a natural mineral; composed of base metal alloy (likely zinc or brass) and epoxy resin/enamel.
Cullet Glass (Man-made Glass Slag)
Amorphous Silica (SiO2) with chemical additives
Chalk
CaCO3 (primarily Calcium Carbonate), biogenic sedimentary rock
Chert (Chocolate or Brown Flint)
Chert (SiO2)
Flint
Sedimentary cryptocrystalline quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Gabbro
Gabbro
White Marble
Recrystallized Calcite Rock (CaCO3)
Sandstone
Arenite (SiO2 primarily)
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
Cardstock (Paper)
Cellulose (C6H10O5)n
Riverstone (Sandstone Pebble)
Arenite (SiO2 with various lithic fragments)
Chert
Sedimentary cryptocrystalline quartz (SiO2)
Coquina
Bioclastic Limestone (Calcium Carbonate, CaCO3)
Orange glassy slag (industrial by-product)
Iron-rich silicate glass; composition varies, commonly Fe–Ca–Al silicate
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (Calcium Carbonate, CaCO3)
Chert Arrowhead (Lithic Tool)
Microcrystalline quartz (SiO2) - Archeological lithic artifact
Tumbled amber-colored chalcedony or jasper
Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper
Red glassy cabochon, likely synthetic ruby or red glass
Uncertain; possible synthetic corundum (Al₂O₃, chromium-colored) or man-made glass
Tumbled opalite (likely synthetic glass)
Opalite; typically man-made opalescent soda-lime glass, not a recognized mineral species
Goldstone (Red/Brown)
Aventurine Glass (SiO2 with Copper inclusions)
Dark gneiss or migmatitic amphibolite
Band ed gneiss; composition likely quartz–feldspar–biotite/amphibole, possibly migmatite
Chert Pebble
Chert (Microcrystalline Quartz, SiO2)
Chert with Limestone
Silicon Dioxide (SiO2) in Calcium Carbonate (CaCO3) Matrix
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Goldstone
N/A (Synthetic Glass with Copper Inclusions)
Granite
Plutonic Igneous Rock (composed typically of SiO2, Al2O3, K2O, Na2O, CaO)
Blue Chalcedony Cube
Silicon Dioxide (SiO2)
Pink Granite
Phaneritic Felsic Igneous Rock (Granite)
Chert (specifically Flint or Common Chert node)
Silicon Dioxide (SiO2)