Limestone
Calcium carbonate (CaCO3)
Category
Browse organic material (likely a fruit or berry) specimens identified by the Rock Identifier community.
Limestone
Calcium carbonate (CaCO3)
Limestone
Calcium Carbonate (CaCO3)
Jade (likely Nephrite Jade based on appearance)
Nephrite (a variety of actinolite, Ca2(Mg,Fe)5Si8O22(OH)2)
Chert (Common Opal variant)
Microcrystalline Quartz (SiO2)
Slate
Slate (Foliated Metamorphic Rock)
Chert (varieties include Flint and Jasper)
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Chert (varieties: Flint or Chalcedony)
Microcrystalline silica (SiO2)
Siltstone
Siltstone (composed of microscopic silt-sized particles of quartz and feldspar)
Jasper
Silicon Dioxide (SiO2)
Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Chert (variations include Flint/Jasper)
Chert (SiO2)
Diamond
Natural Carbon (C)
Basalt (River Pebble)
Basalt
Biotite on Matrix
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Brachiopod Fossil
Phylum Brachiopoda (likely Order Rhynchonellida or Spiriferida)
Orange Quartz with Epidote
Silicon Dioxide (SiO2) with Calcium Aluminum Iron Silicate hydroxide (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))
Scoria (Basaltic Lava Rock)
Vesicular Basalt
Muscovite Mica
Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2
Green Calcite (Onyx Marble)
Calcium Carbonate (CaCO3)
Jasper
Agate/Jasper (Microcrystalline Quartz, SiO2)
Quartz Geode
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Rough Diamond
Diamond (pure carbon, C)
Limestone
Calcite (CaCO3)
Fossilized Gastropod (Snail)
Class Gastropoda (internal mold or 'steinkern')
Milky Quartz
Silicon Dioxide (SiO2)
Red Sandstone
Arenite (primarily Quartz with Iron Oxide)
Basalt
Extrusive mafic igneous rock
Sandstone (Fossiliferous)
Clastic Sedimentary Rock (primarily SiO2)
Siltstone
Siltstone (primarily SiO2, Al2O3)
Pink Garnet (likely Almandine or Rhodolite)
Garnet Group (Fe3Al2(SiO4)3 to Mg3Al2(SiO4)3)
Olivine (Peridotite)
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
Sandstone
Arenite (SiO2 based with various cements)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Ironstone (likely Ferruginous Siltstone/Sandstone)
Ferruginous sedimentary rock (FeOx-rich clastic)
Quartz Geode
Silicon Dioxide (SiO2) in Host Rock
Milky Quartz
Silicon Dioxide (SiO2)