Sandstone
Arenite (SiO2 primarily)
Category
Browse man made rock (sedimentary analogue) specimens identified by the Rock Identifier community.
Sandstone
Arenite (SiO2 primarily)
Limestone with Calcite Veins
Calcium Carbonate (CaCO3)
Glauconitic Sandstone
Glauconitic Sandstone (contains (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Ferruginous Sandstone
Arenite with Hematite/Limonite cement (SiO2 + Fe2O3)
Limestone with Quartz or Calcite Veining
Calcium Carbonate (CaCO3) matrix with SiO2 or CaCO3 inclusions
Red Carnelian
Carnelian (Silicon Dioxide, SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO₂)
Herkimer Diamond
Quartz (Silicon Dioxide, SiO2)
Quartz (Drusy/Crystalline variety)
Silicon Dioxide (SiO2)
Banded Agate (Tumbled)
Cryptocrystalline Quartz (SiO2)
Milky Quartz (Vein Quartz)
Silicon Dioxide (SiO2)
Carnelian Agate
Carnelian (Silicon Dioxide: SiO2)
Slate
Foliated Metamorphic Rock (composed primarily of Quartz, Muscovite, and Illite)
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
Opal
Hydrated Silica (SiO2·nH2O)
Geode with Quartz and Chalcedony
Silicon Dioxide (SiO2)
Ferruginous Sandstone (Ironstone)
Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)
Common Opal with Host Rock
Opal (Hydrated silica, SiO2·nH2O)
Schist
Chlorite/Mica Schist
Gneiss
Gneiss (high-grade metamorphic rock typically composed of quartz, feldspar, and mica)
Quartz Geode
Silicon Dioxide (SiO2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Chert / Flint
Chert (Silicon Dioxide, SiO2)
Ironstone Concretion
Siderite or Limonite Concretion
Chert (Nodule)
Silicon Dioxide (SiO2)
Red Brecciated Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Jasper
Silicon Dioxide (SiO2)
Travertine
Travertine (CaCO3 - Calcium Carbonate)
Dalmatian Stone
Dalmatian Jasper (Aplitic Perthite)
Painted River Pebble (likely Basalt or Greywacke)
Aphanitic Lithic Clast with Anthropogenic Pigment coating
Boxwork Siderite or Sepatarian Nodule Weathering
Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment
Sandstone (Ferruginous)
Ferruginous Sandstone (SiO2 with Fe2O3/FeO(OH) cement)
Agate (Banded Chalcedony)
Cryptocrystalline Silica (SiO2)
Dolomite or Limestone (Carbonate Rock)
CaMg(CO3)2 (Dolomite) or CaCO3 (Limestone / Calcite)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Red Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Microcrystalline Quartz with Iron Oxide impurities (Hematite)
Grey River Stone (Gneiss/Schist mix)
Foliated Metamorphic Rock (variable mineral formula)
River Rock (Gneiss/Schist mix)
Foliated Metamorphic Rock (Gneiss)
Gneiss
Gneiss
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Specular Hematite
Hematite (Fe2O3)