Piddock-bored Mudstone
Lutite (Siltstone or Mudstone) with Pholad borings
Category
Browse man made byproduct (non geological) specimens identified by the Rock Identifier community.
Piddock-bored Mudstone
Lutite (Siltstone or Mudstone) with Pholad borings
Metaconglomerate
Protolith: Conglomerate (comprising SiO2, Al2O3, etc.)
Obsidian
Obsidian (volcanic glass)
Obsidian
Volcanic Glass (Primary component: SiO2)
Obsidian
Obsidian (Volcanic Glass)
Quartzite
Quartzite (Primary mineral: SiO2)
Obsidian
Volcanic Glass (SiO2)
Conglomerate
Conglomerate (clastic sedimentary rock)
Quartzite
Quartzite (primarily SiO2)
Amber
Succinite (fossilized resin); C10H16O
Rainbow Obsidian
Volcanic glass (SiO2 - approximately 70% or more silicon dioxide)
Obsidian
Obsidian (Amorphous volcanic glass, SiO2 with impurities)
Limonite Pseudomorph after Pyrite
Limonite (Hydrous iron oxides, FeO(OH)·nH2O) replacing Pyrite (FeS2)
Shale (with minor calcite veining)
Clastic sedimentary rock (primarily clay minerals and quartz)
Obsidian
Obsidian (Volcanic glass), SiO2 (major component)
BROWN GRANITE (likely 'Tan Brown' or similar)
Granite (specifically a variety rich in orthoclase feldspar, often with biotite and possibly hornblende)
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Black Obsidian
Volcanic Glass (Amorphous Silicon Dioxide SiO2)
Obsidian with Mahogany Phasing
Volcanic Glass (SiO2 + Fe2O3)
Amber
Succinite (specific to Baltic amber), fossilized tree resin
Chalcedony (or a variety of Chalcedony, likely Agate or Jasper)
Chalcedony (SiO₂)
Black Obsidian
Volcanic Glass (SiO2 + impurities)
Obsidian
Volcanic Glass (SiO2 + impurities)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Volcanic Glass (predominantly SiO2)
Clay Brick
Ceramic structural unit (Al2O3·2SiO2·2H2O as precursor)
Porcelain (Kaolin-based)
Alumina silicate ceramic (composed primarily of Kaolinite: Al2Si2O5(OH)4)
Chalk
CaCO3 (primarily Calcium Carbonate), biogenic sedimentary rock
Obsidian (Black Obsidian)
Amorphous volcanic glass (primarily SiO2)
Conglomerate
Conglomerate (SiO2, Al2O3, Fe2O3, CaCo3)
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Obsidian (Volcanic Glass, SiO2)
River Pebble (Greywacke or Quartzite-rich Sandstone)
Lithic Sandstone (primarily SiO2 with rock fragments)
Fossiliferous Limestone
Limestone (composed primarily of calcite with included fossils CaCO3)
Obsidian
Volcanic Glass (SiO2)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Quartzite
Quartzite (composed primarily of SiO2)