Sandstone (Ferruginous)
Sandstone (mainly SiO2 with Fe2O3 staining)
sedimentary
Category
Organic Gem Material (Botanical)
Browse organic gem material (botanical) specimens identified by the Rock Identifier community.
Opalite
Man-made Glass (SiO2 + additives)
mineraloid (synthetic)
Limonite
FeO(OH)·nH2O (Hydrated iron oxide)
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Opalite (Synthetic Moonstone/Sea Opal)
Silicon Dioxide (SiO2) glass with metallic inclusions
Synthetic/Man-made Glass
Ocean Jasper
Orbicular Jasper (Silicon Dioxide - SiO2)
sedimentary
Limestone
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Tiger Iron
Tiger Iron (composite of Tiger's Eye, Red Jasper, and Hematite)
metamorphic
Cubic Zirconia (Simulated Diamond)
Zirconium dioxide (ZrO2)
mineral
Chalcedony (specifically Blue Chalcedony or Common Opal variety)
Silicon Dioxide (SiO₂)
mineral
Jasper
Silicon dioxide (SiO2)
sedimentary
Concrete
Anthropogenic Sedimentary Conglomerate (Cement mixture: typically Ca2SiO4, Ca3SiO5, Ca3Al2O6)
sedimentary (artificial)
Stichtite in Serpentine (Atlantisite)
Mg6Cr2CO3(OH)16·4H2O (Stichtite) within Mg3Si2O5(OH)4 (Serpentine)
metamorphic
Sedimentary Breccia
Clastic Breccia (CaCO3/SiO2 matrix)
sedimentary
Concrete
Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)
sedimentary (anthropogenic / man-made)
Chert (Common Opal/Jasper variety)
Cryptocrystalline Quartz (SiO2)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Chert (Flint Nodules)
Cryptocrystalline Quartz (SiO2)
sedimentary
Obsidian
Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)
igneous
Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
sedimentary
Chert (specifically Gray Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Banded Chert (Agate-like Flint)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Chert (often called Flint or Jasper)
Silicon Dioxide (SiO2)
sedimentary
Chert (variations include Flint or Jasper)
Chert (Silicon Dioxide, SiO2)
sedimentary
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
sedimentary
Ocean Jasper
Orbicular Jasper (Silicon Dioxide SiO2)
sedimentary
Amethyst
Quartz (SiO2) variety
Mineral
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Chert (varietal Flint or Jasper)
Silicon Dioxide (SiO2)
sedimentary
Banded Calcite (often sold as 'Mexican Onyx')
Calcite (Calcium Carbonate - CaCO3)
sedimentary
Uraninite (Pitchblende)
Uranium dioxide (UO2)
mineral
Ferruginous Conglomerate
Conglomerate with Iron-Oxide Matrix (SiO2 + Fe2O3/FeO(OH))
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Flint (Chert)
Cryptocrystalline Quartz (SiO2)
sedimentary
Porcelain (White Ceramic)
Mullite-bearing Vitrified Ceramic (Major phases: Mullite Al6Si2O13, Glassy Silica SiO2)
metamorphic
Ferruginous Sandstone (Gozzan)
Iron-rich clastic sedimentary rock with Limonite/Goethite
sedimentary
Diamond
Diamond (C)
mineral
Green Calcite (Onyx Marble)
Calcium Carbonate (CaCO3)
mineral
Chert (variations include Flint/Jasper)
Cryptocrystalline Quartz (SiO2)
sedimentary
Ferruginous Sandstone (Ironstone)
Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Slate
Metamorphosed Shale (Fine-grained Foliated Metamorphic Rock)
metamorphic
Diamond
Carbon (C)
mineral