Sandstone
Arenite (primarily SiO2)
Category
Browse man made object (metalwork) specimens identified by the Rock Identifier community.
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Sandstone (Pet Rock)
Clastic sedimentary rock (primarily SiO2)
Diamond
C (Pure Carbon)
Chert / Flint
Silicon Dioxide (SiO2)
Tumbled greenstone, likely nephrite jade
Nephrite jade (interlocking tremolite–actinolite amphibole; Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂)
Chert
Microcrystalline quartz (SiO2)
Limestone
Calcareous sedimentary rock (CaCO3)
Chalk
Calcite (CaCO3)
Sandstone
Arenite (specifically sublithic or quartz arenite)
Chalcedony (Common Opal or Agate variant)
Silicon dioxide (SiO2) with trace hydration
Peanut Wood
Petrified Wood (Silicified Araucaria with Teredo boreholes)
Chert
Microcrystalline Quartz (SiO2)
Fossilized Shark Tooth (Eroded)
Carcharodon sp. or Otodus sp. fragment (likely)
Red Sandstone
Arenite (Fe2O3 enriched)
Fossiliferous Limestone (Crinoid stem fossils)
Sedimentary Limestone with Crinoidea ossicles
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Granodiorite
Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)
Jasper (Iron-rich Chalcedony)
Jasper (Microcrystalline Silicon Dioxide, SiO2 plus iron oxide impurities)
Obsidian
Obsidian (Volcanic Glass)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Chert (Yellow/Tan variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Blue Chalcedony
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Amethyst
Amethyst (Silicon Dioxide - SiO2 with Iron impurities)
Chert Arrowhead
Microcrystalline Quartz (SiO2)
Bivalve Fossil (Shell Fragment)
Class Bivalvia (Calcium Carbonate - CaCO3)
Banded Chert
Microcrystalline Quartz (SiO2)
Chert Nodule (Flint)
Chert (Silicon Dioxide, SiO2)
Diamond
Diamond (Pure Carbon, C)
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Polished ocean jasper or orbicular chalcedony
Microcrystalline quartz (SiO₂), likely chalcedony with feldspar or other mineral inclusions
Petoskey Stone
Hexagonaria percarinata
Chert / Flint
Microcrystalline Quartz (SiO2)
Porphyry
Porphyritic Igneous Rock
Sandstone (Pebble)
Sandstone (SiO2 with matrix/cement)
Aventurine
Aventurine Quartz (SiO2 with inclusions of Fuchsite)
Slate
Slate (Foliated Metamorphic Rock)
Chert (varieties: Flint or Jasper)
Silicon dioxide (SiO2) / Microcrystalline Quartz
Diamond
Carbon (C)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)