Granite Cobble
Granitic intrusive igneous rock (Quartz, Feldspar, Mica)
Category
Browse not a rock (man made origin) specimens identified by the Rock Identifier community.
Granite Cobble
Granitic intrusive igneous rock (Quartz, Feldspar, Mica)
Sandstone
Arenite
White Marble
Recrystallized Calcite (CaCO3)
Polished red gemstone pendant, likely red jasper or brecciated jasper
Jasper: microcrystalline quartz (SiO₂), commonly with hematite or iron-oxide inclusions
Sandstone
Arenite (variable SiO2 composition)
Sandstone
Sedimentary Clastic Rock (Quartzose Sandstone)
Quartz (Milky/Yellowish Pebble)
Silicon Dioxide (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Chert (Flint)
SiO2 (Microcrystalline Quartz)
Man-made Jewelry Charm (Enameled Metal)
Not a natural mineral; composed of base metal alloy (likely zinc or brass) and epoxy resin/enamel.
Sandstone
Arenite (primarily SiO2)
Sandstone (Quartz Arenite)
Sandstone (dominated by SiO2 quartz grains)
Bivalve Fossil (Shell Fragment)
Class Bivalvia (Calcium Carbonate - CaCO3)
Fossil bivalve shell
Likely an internal mold or mineralized shell of a brachiopod or small bivalve; exact taxonomy requires locality and diagnostic details
Amber
Fossilized tree resin (Amorphous organic polymer)
Lapis Lazuli
Lapis Lazuli (Complex aggregate mainly of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Basalt
Basalt (Mafic volcanic rock)
Lapis Lazuli
Lapis Lazuli (Rock composed primarily of Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)
Tumbled brown chalcedony (likely jasper or agate)
Microcrystalline quartz, SiO₂; chalcedony with iron-oxide staining
Quartz (Clear Quartz/Rock Crystal)
Silicon Dioxide (SiO2)
Cullet Glass (Strawberry Glass)
Amorphous Silicon Dioxide (SiO2) with metallic dopants
Granite
Granite (plutonic igneous rock)
Bauxite (Laterite Clay)
Bauxite (mixture of Hydrous Aluminum Oxides: Gibbsite Al(OH)3, Boehmite and Diaspore AlO(OH))
Blue Sapphire
Corundum (Al2O3 - Aluminum Oxide)
Fluorite
Calcium fluoride (CaF2)
Fluorite Cleavage Octahedron
Fluorite (Calcium Fluoride, CaF2)
Green Fluorite
Calcium Fluoride (CaF2)
Green Fluorite
Calcium Fluoride (CaF2)
Fluorite
Calcium Fluoride (CaF2)
Fluorite
Calcium Fluoride (CaF2)
Fluorite
Calcium Fluoride (CaF2)
Fluorite
Calcium Fluoride (CaF2)
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
Fluorite
Calcium Fluoride (CaF2)
Ferruginous Sandstone with Quartz Inclusions
Clastic Sedimentary Rock (Iron-rich Sandstone)
Chert Arrowhead
Cryptocrystalline Quartz (SiO2)
Native Silver
Silver (elemental Ag)
Pearl
Calcium Carbonate (CaCO3) - mainly Aragonite and Calcite
Quartzite
Metamorphic Quartzite (SiO2)
Chert (Flint / Jasper variant)
Microcrystalline Quartz (SiO2)
Marble
Metamorphic Limestone (CaCO3)
Pearl (incorporated into jewelry)
Aragonite and Calcite (CaCO3)