Siltstone
Siltstone (fined-grained clastic sedimentary rock)
Category
Browse organic (non rock) specimens identified by the Rock Identifier community.
Siltstone
Siltstone (fined-grained clastic sedimentary rock)
Snowflake Obsidian
Hydrated Volcanic Glass with Cristobalite inclusions
Quartzite Beach Pebble
Metamorphosed Quartz Sandstone (SiO2)
Snowflake Obsidian
Volcanic glass containing Spherulites of Cristobalite (SiO2)
Breccia
Clastic Breccia (SiO2/CaCO3 dominated)
Weathered quartz-rich metamorphic rock, likely quartzite
Quartzite; predominantly crystalline SiO₂, possibly with mica or feldspar
Serpentinite
Serpentinite (group of hydrous magnesium iron phyllosilicates)
Mahogany Obsidian
Volcanic Glass with Hematite or Magnetite inclusions (SiO2 + Fe2O3)
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
Quartzite
Quartzite (primarily SiO2)
Poppy Jasper
Microcrystalline Quartz (SiO2) with mineral inclusions
Chert Nodules in Limestone
Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)
Quartzite
Quartzite (SiO2)
Quartzite
Quartzite (SiO2)
Quartzite
Metamorphic Quartzite (primarily SiO2)
Quartzite
Quartzite (primarily SiO2)
Sandstone
Sandstone (principally SiO2/Silicon Dioxide)
Chert (specifically Jasper/Flint)
Microcrystalline Quartz (SiO2)
Chert (and Flint)
Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Quartzite Pebble
Metamorphic Quartz (SiO2)
Quartzite Cobble with Iron Staining
Metamorphosed Quartz Sandstone (SiO2)
Smurf Rock (Fictional Interpretation)
Cyanus Anthropomorphicus (Geologic Simulation)
Amber
Succinite (formula varies, primarily C10H16O)
Red Siltstone (or Red Shale)
Clastic Sedimentary Rock (Composition: primarily Quartz, Clay minerals, and Hematite Fe2O3)
Sandstone with Liesegang Rings
Clastic Sedimentary Rock with Iron Oxide Precipitates (SiO2 + Fe2O3)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Quartzite
Silicon Dioxide (SiO2)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Apache Tear
Obsidian (Hydrated Volcanic Glass) - SiO2 (with impurities)
Chert (Flint)
Chert (SiO2)
Quartzite Pebble
Quartzite (primarily SiO2)
Obsidian
Volcanic Glass (SiO2)
Opal
Hydrated Silica (SiO2·nH2O)
Obsidian (Polished)
Obsidian (Volcanic glass, primarily SiO2)
Obsidian
Obsidian (volcanic glass), amorphous SiO2 + impurities
Precious Opal
Hydrated silica (SiO2·nH2O)
Snowflake Obsidian
Volcanic Glass with Spherulite Inclusions (primarily SiO2)
Basalt
Basalt
Slag
Anthropogenic Vitreous Silica/Iron oxides
Granodiorite
Granodiorite (intermediate plutonic rock)
Opal
Hydrated silica (SiO2 "NH2O)