Chert (and/or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse synthetic (man made glass) specimens identified by the Rock Identifier community.
Chert (and/or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (variations include Flint/Jasper)
Cryptocrystalline Quartz (SiO2)
Diamond
Diamond (pure Carbon, C)
Silver (Jewelry form)
Native Silver (Ag)
Breccia
Breccia
Sandstone
Arenite (composed primarily of Quartz: SiO2)
Diorite
Diorite (Plagioclase feldspar and amphibole/biotite)
Greenstone
Metamorphic mafic rock (chlorite-actinolite-epidote schist)
Sandstone
Sandstone (composed predominantly of Quartz, SiO2, with Feldspar and Clay minerals)
Malachite
Malachite (Cu2CO3(OH)2)
Swirled Agate Bead
Silicon Dioxide (SiO2)
Marble
Metamorphic Limestone (CaCO3)
Rough Diamond
Diamond (pure Carbon, C)
Natural Pearl (appearing in a jewelry setting)
Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin
Amethyst (Tumbled Cabinet Stone)
Silicon Dioxide (SiO2) with iron impurities
Pink Granite
Intrusive Igneous Rock (high K-feldspar content)
Diorite
Diorite (Intermediate intrusive igneous rock)
Chert
Cryptocrystalline Quartz (SiO2)
Diamond
Native Carbon (C)
Chert (Nodule)
Chert (Silicon Dioxide, SiO2)
Granite
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Coquina (Fossiliferous Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
Blue calcite sphere
Calcite (CaCO₃), commonly blue-calcite variety
Sandstone (Pebble)
Arenite
Granite
Phaneritic Felsic Igneous Rock
Granite
Granite (Felsic Plutonic Rock)
Chert (Flint)
Microcrystalline quartz (SiO2)
Black Tourmaline (Schorl)
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Rutilated Quartz
Quartz (SiO2) with Rutile inclusions (TiO2)
Moonstone
Orthoclase Feldspar (KAlSi3O8)
Chert
Microcrystalline quartz (SiO2)
Petoskey Stone
Favosites alpenensis
Graphite
Graphite (Carbon, C)
Sandstone
Sandstone (clastic sedimentary rock, predominantly SiO2)
Diamond
Carbon (C)
Nephrite Jade
Ca2(Mg, Fe)5Si8O22(OH)2
Chert (Green Chert or Jasper)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Granite
Phaneritic Igneous Rock (primarily SiO2, Al2O3, K2O, Na2O)
Sandstone
Clastic Sedimentary Rock
Dumortierite in Quartz
Dumortierite (Al6O3(BO3)(SiO4)3) with Quartz (SiO2)