Sodalite
Sodalite (Na4Al3Si3O12Cl)
Mineral
Category
Organic (Geological Relative)
Browse organic (geological relative) specimens identified by the Rock Identifier community.
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Jasper
Silicon Dioxide (Microcrystalline Quartz / Chalcedony)
sedimentary
Sandstone Pebble (River Rock)
Sandstone (Quartz-rich sedimentary rock with iron oxide staining)
sedimentary
Black Marble with Quartz Veining
Metamorphosed Limestone (Recrystallized CaCO3)
metamorphic
Red Sandstone with Reduction Spot
Quartzose Sandstone with a Leach/Reduction Spot
sedimentary
Sandstone (with carbonaceous plant fragments)
Arenite (composed primarily of SiO2)
sedimentary
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
sedimentary
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
igneous
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
Mineral (Variety of Chalcedony)
Hardpan Nodule / Ferruginous Sandstone
Ferruginous Sandstone (Fe-cemented sediment)
sedimentary
Chert with Calcite Veining
Microcrystalline Quartz (SiO2) with Calcium Carbonate (CaCO3) veins
sedimentary
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Mineral
Quartz
Silicon Dioxide (SiO2)
Mineral
Prehnite
Prehnite, Ca2Al2Si3O10(OH)2
Mineral
Pyrite
Iron Pyrite (FeS2)
mineral
Seraphinite
Clinochlore (a variety of the chlorite group)
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Black Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Basaltic Tuff / Volcanic Breccia
Pyroclastic Breccia / Lithic Tuff
igneous
Quartz Geode
Silicon Dioxide (SiO2)
sedimentary
Ambergris (Marine Coprolite/Subfossil)
Marine organic coprolite / Ambergris (Physeter macrocephalus metabolite)
fossil
Quartz (Pebble)
Quartz (SiO₂)
Mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Peridot (Olivine)
Olivine, (Mg,Fe)2SiO4
Mineral
Sandstone with Trace Fossils
Quartz Arenite with Bioturbation (Trace Fossils)
sedimentary
Cobaltoan Calcite / Pink Dolomite (Possible)
Cobaltoan Calcite: (Ca,Co)CO3; Pink Dolomite (or Thulite): CaMg(CO3)2 or Mn-Dolomite / (Thulite: Mn2+3Al2(Si2O7)(SiO4)O(OH))
Mineral / Rock (depending on purity)
Opalite
Synthetic Opalised Glass
Mineral (Synthetic / Man-made)
Carved Mottled Greenish-Yellow Crystal/Glass Object
Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.
Man-made Object/Uncertain Mineral
Petrified Wood
Silicified wood (Quartz / Chalcedonized wood, SiO2)
sedimentary
Graphite
Graphite (Carbon, C)
Mineral
Chert (with Quartz vein)
Chert (Silicon Dioxide, SiO2)
sedimentary
Quartz (pebble)
Quartz (SiO₂)
Mineral
Quartz Geode
Silicon Dioxide (SiO2) within a secondary sedimentary structure
sedimentary
Quartz
Quartz (SiO₂)
Mineral
Arsenopyrite in Quartz Matrix
Arsenopyrite (FeAsS) with Quartz (SiO2)
Mineral in a Metamorphic/Hydrothermal rock
Petrified Wood
Silicified Wood (primarily quartz/chalcedony replacing organic wood structure, SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily quartz/chalcedony replacing organic wood structures, SiO2)
fossil
Fossilized Horn Coral
Rugosa (Tetracoralla)
fossil
Zebra Marble
Metamorphosed Alabaster/Limestone (CaCO3)
metamorphic
Ambergris
Physeter macrocephalus excreta (Ambergris)
mineraloid / organic geological find
Pyrite
Pyrite (Iron Disulfide), FeS2
Mineral