Tumbled greenstone, likely nephrite jade
Nephrite jade (interlocking tremolite–actinolite amphibole; Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂)
Category
Browse man made object (ring) specimens identified by the Rock Identifier community.
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 (Flint)
Cryptocrystalline Quartz (SiO2)
Carnelian
Carnelian (Chalcedony / SiO2)
Carnelian Agate
Carnelian (Silicon Dioxide - SiO2)
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)
Chert (varieties: Flint or Jasper)
Silicon dioxide (SiO2) / Microcrystalline Quartz
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Marble
Recrystallized Calcite (CaCO3)
Diabase (Dolerite)
Diabase
Banded Chert (River Stone)
Silicon Dioxide (SiO2)
Diamond
Carbon (C)
Sandstone
Arenite (SiO2 based typically)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite