Coarse-grained Granite
Phaneritic Granite (contains Quartz, Feldspar, and Mica)
Category
Browse biogenic material specimens identified by the Rock Identifier community.
Coarse-grained Granite
Phaneritic Granite (contains Quartz, Feldspar, and Mica)
Flagstone (Sandstone)
Clastic Sedimentary Rock (composed of quartz and feldspar)
Quartzite
Quartzite (SiO2)
Fossiliferous limestone
Calcarenite/bioclastic limestone, predominantly calcite (CaCO₃)
Tumbled honey calcite (likely aragonite/calcite material)
Calcite, CaCO₃; possibly aragonite, a polymorph of CaCO₃
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Likely petrified wood
Silicified wood, chiefly microcrystalline quartz (SiO₂)
Tumbled rose quartz
Quartz (SiO₂), pink variety
Red Jasper
Silicon Dioxide with Hematite (SiO2 + Fe2O3)
Flint
Microcrystalline Quartz (SiO2)
Flint
SiO2 (Cryptocrystalline Quartz)
Agate
Silicon Dioxide (SiO2)
Chert / Flint
Silicon Dioxide (Microcrystalline Quartz, SiO2)
Gravel and Sediment Sample
Mixed clastic sediment
Flint
Silicon dioxide (SiO2)
Chert (Flint/Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert (Arrowheads)
Microcrystalline Quartz (SiO2)
Chondrite Meteorite
L or H Ordinary Chondrite
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Chert (Jasper/Flint variant)
Microcrystalline Quartz (SiO2)
Crushed Stone (Likely Limestone or Granite)
Calcium Carbonate (CaCO3) for Limestone / Quartz and Feldspar for Granite
Chert (Flint Nodules)
Silicon Dioxide (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline quartz (SiO2)
Banded Chert
Silicon Dioxide (SiO2)
Iron Meteorite
Siderite (Iron-Nickel Meteorite)
Chert (often called Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Lava Rock with Fabric Impression
Scoria or Basalt with anthropogenic impressions
Tumbled smoky quartz
Quartz (SiO₂), smoky variety
Translucent agate/chalcedony
Microcrystalline quartz (SiO₂), likely chalcedony with agate-like banding
Chert (Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Common Jasper/Flint)
Microcrystalline Quartz (SiO2)
Diamond
Carbon (C)
Sandstone with Iron Staining
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
Sandstone
Arenite (SiO2 primarily)
Shale
Mudrock / Fissile Shale
Turquoise (possible Howlite imitation)
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Tumbled jasper (likely brecciated or orbicular jasper)
Microcrystalline quartz (SiO₂), with iron-oxide inclusions
Agate and Chalcedony Beads
Cryptocrystalline Quartz (SiO2)
Chinese Jade (Green Nephrite or Jadeite)
Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)
Laterite (Red Clay)
Laterite (Fe2O3 · nH2O and Al2O3 · nH2O)
Basalt
Aphanitic basaltic rock