Fossilized Horn Coral
Order Rugosa (Rugose Coral)
Category
Browse organic (non rock) specimens identified by the Rock Identifier community.
Fossilized Horn Coral
Order Rugosa (Rugose Coral)
Chert (often called Jasper or River Rock)
Chert (SiO2)
Siltstone with Quartz Vein
Siltstone (primarily SiO2, Al2O3, Fe2O3)
Conglomerate
Conglomerate (Sedimentary rock containing rounded clasts)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)
Chert (variously identified as Flint)
Microcrystalline Quartz (SiO2)
Sandstone Chert Concretion
Silica-cemented Concretion (primarily SiO2)
Chert (Chert / Flint)
Silicon dioxide (SiO2) - Microcrystalline quartz
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Brecciated or Veined)
Silicon Dioxide (SiO2)
Anthracite Coal
Anthracite (Carbon-based sedimentary-derived metamorphic rock)
Opalite (Man-made Glass)
Synthetic Silicon Dioxide Glass (SiO2 + metal oxides)
Dyed Pink Quartzite (Jadeite Simulant)
Silicon Dioxide (SiO2) with organic dye
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Chert with Quartz Veining
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (70–75% SiO2)
Fossilized Coral
Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)
Petrified Wood
Silicified Wood (SiO2)
Conglomerate (Red Sandstone variety)
Clastic Sedimentary Rock (Conglomeratic Sandstone)
Baltic Amber (Butterscotch variety)
Succinite
Pumice
Pumice (Vesicular Volcanic Glass)
Petrified Wood
Silicified Wood (primarily Chalcedony or Quartz, SiO2)
Chert (and/or River Pebble)
Microcrystalline silica (SiO2)
Slag
Ferrous Slag (Amorphous calcium-magnesium-aluminum silicates)
Red Quartzite River Stone
Metamorphic Rock (composed mainly of Quartz, SiO2)
Moss Agate
Chalcedony (SiO2) with inclusions of hornblende or chlorite
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Quartzite (or Ferruginous Quartzite)
Metamorphosed Quartz Sandstone (SiO2 with Fe2O3 impurities)
Coal (Bituminous or Anthracite)
Carbonaceous sedimentary rock (primarily Carbon, C)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Nodular)
Microcrystalline Silica (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Banded Chert (River Siltstone)
Microcrystalline Quartz (SiO2)
Chert (Arrowhead/Artifact Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (with Quartz vein)
Chert (Silicon Dioxide, SiO2)
Crinoid Fossil in Limestone
Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)
Quartzite River Rock
Quartzite (primarily SiO2)
Chert (Nodular Chert)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Moss Agate
Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)