Diamond (in jewelry mount)
Carbon (C)
Category
Browse marble specimens identified by the Rock Identifier community.
Diamond (in jewelry mount)
Carbon (C)
Chert (Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Fossil Shark Tooth
Carcharocles (Otodus) sp. or similar fossilized Chondrichthyes tooth
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Hag Stone
Naturally holed stone (typically sedimentary rock such as flint, limestone, or sandstone)
Crinoid Fossil in Chert
Crinoid (Class Crinoidea) in Microcrystalline Quartz (SiO2)
Chert Nodules
Chert (Silicon Dioxide, SiO2)
Serpentine (Nephrite-like River Cobble)
Serpentinite (Hydrous Magnesium Iron Silicate)
Chert with Iron Staining
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Limonite (Iron Ore)
Limonite (Hydrated iron oxide - FeO(OH)·nH2O)
Sandstone
Arenite (SiO2 based)
Limestone
Calcium Carbonate (CaCO3)
Chert (Tan/Yellow variety)
Microcrystalline Quartz (SiO2)
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
Chert (and Limestone)
Silicon Dioxide (SiO2)
Rough Diamond
Diamond (pure carbon, C)
Diamond (in a gold setting)
Carbon (C)
Crinoid Stem Fossil in Matrix
Crinoid (Class Crinoidea) in Limestone/Siltstone matrix
Coquina
Bioclastic Limestone (composed primarily of Calcium Carbonate / CaCO3)
Limestone Pebble
Limestone (Calcium Carbonate, CaCO3)
Chert (concretionary/nodular variant)
Microcrystalline Quartz (SiO2) with possible fossil or mineral inclusions
Horn Coral Fossil
Rugosa (Order Rugosa)
Limestone
Calcium Carbonate (CaCO3)
Chert (Flint)
Chert (Cryptocrystalline Silicon Dioxide, SiO2)
Honeycomb Coral Fossil
Favosites (extinct genus of tabulate coral)
Chert (and Jasper pebble)
Microcrystalline Silica (SiO2)
Chert (Jasper/Limonitic Chert)
Silicon dioxide (SiO2)
Gastropod Internal Mold (Steinkern)
Class Gastropoda fossil mold (Phylum Mollusca)
Serpentinite
Serpentinite (composed primarily of minerals in the Serpentine group: Chrysotile, Lizardite, and Antigorite)
Basalt Pebble
Basalt (Extrusive Mafic Igneous)
Sandstone (Ferruginous)
Clastic Sedimentary Rock (Litharenite)
Chert (Serpentinized)
Silicon Dioxide (SiO2) with mineral staining
Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Mookaite Jasper
Siliceous (chert) sedimentary rock, a form of Jasper
Sandstone (Pebble/Cobble)
Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)
Peridot (likely, given the color and bead form)
Olivine, variety Peridot (Mg,Fe)2SiO4
Fossil Shark Tooth
Odontaspididae (likely Carcharias sp.)
Fossilized Tabulate Coral in Sandstone/Limestone
Favosites (Order: Tabulata)
Chert (variations include Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Serpentine
Antigorite/Chrysotile group ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al,Fe)2O5(OH)4)