Greenstone
Greenschist (composed of actinolite, chlorite, and epidote)
Category
Browse organic (if resin) or synthetic (if glass); simulating sedimentary or metamorphic (for natural stones) specimens identified by the Rock Identifier community.
Greenstone
Greenschist (composed of actinolite, chlorite, and epidote)
Chalcedony (Quartz Nodule)
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite (Iron-rich)
Yellow Chert or Jasper
Microcrystalline Quartz (SiO2)
Ferruginous Sandstone
Sandstone, Iron-rich
Sandstone (likely Calcareous or Quartz-rich)
Arenite (SiO2 based typically)
Ambergris (Geological/Organic Specimen)
Ambra grisea (Produced by Physeter macrocephalus)
Geode (Unbroken)
Silicon Dioxide (SiO2) usually as Microcrystalline Quartz or Chalcedony
Chert (often called Flint or Jasper if reddish)
Microcrystalline Quartz (SiO2)
Blue Apatite
Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)
Sandstone (Weathered Pebble)
Arenite (primarily SiO2)
Chert (with small quartz inclusion)
Microcrystalline Silica (SiO2)
Kimberlite
Kimberlite (Potassic ultramafic volcanic rock)
Quartzite Cobble
Quartzite (primarily SiO2)
Basalt (with possible Olivine inclusions)
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Common Opal in Host Rock
Hydrated Silica (SiO2·nH2O)
Yellow Chalcedony (Agate/Jasper mix)
Silicon Dioxide (SiO2)
Chert (Gravel)
Chert (Cryptocrystalline silicon dioxide, SiO2)
Chert (specifically Flint or Jasper variant)
Microcrystalline quartz (SiO2)
Quartzite with Quartz Vein
Metamorphosed Quartz-rich Arenite (SiO2)
Sandstone Concretion
Clastic sedimentary rock (primarily Silica, SiO2, or Calcium Carbonate, CaCO3)
Chlorite Included Quartz
Silicon Dioxide (SiO2) with Chlorite (Mg,Fe,Li)6AlSi3O10(OH)8
Jasper
Jasper (Silicon Dioxide, SiO2)
Aragonite Star Cluster
Aragonite (Sputnik habit) - CaesarCO3
Banded Agate (River-worn Pebble)
Cryptocrystalline Silicon Dioxide (SiO2)
Sandstone (likely Fossiliferous)
Arenite / Sedimentum arenaceum
Sandstone with Secondary Mineral Encrustation
Arenite with Silica/Calcite deposits (SiO2 or CaCO3)
Sandstone (Quartz Sandstone)
Arenite (primarily SiO2)
Jasper with Hematite inclusions
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3)
Chert (Iron-stained)
Chert (SiO2 - Silicon Dioxide)
Sandstone
Arenite (primarily SiO2)
Chalcedony (Agate/Chert variety)
Silicon Dioxide (SiO₂)
Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Iron Gossan (Limonite/Goethite)
Hydrated Iron Oxides (FeO(OH)·nH2O) from oxidation zones
Chert / Jasper
Sedimentary Cryptocrystalline Quartz (SiO2)
Chalcopyrite in Matrix
Chalcopyrite (CuFeS2)
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Chert Nodule (River Cobble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Amethyst (Quartz variety)
Silicon Dioxide (SiO2) with iron impurities
Quartz Geode Pebble
Silicon Dioxide (SiO2)
Schist
Mica Schist
Chalcedony (Botryoidal)
Silicon Dioxide (SiO2) - Microcrystalline Quartz