Chert (variant Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse sedimentary (with some aspects of mineral replacement) specimens identified by the Rock Identifier community.
Chert (variant Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Chalcedony/Agate)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Fossilized coral or carbonate fossil fragment
Calcareous fossil, likely colonial coral (order Hexacorallia; uncertain from image)
Fluorite
Calcium Fluoride (CaF2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Sandstone
Arenite (SiO2 primarily)
Pyrite
Pyrite (Iron sulfide, FeS₂)
Agate Geode
Cryptocrystalline Quartz (SiO2)
Chert (Quartz Variety)
Microcrystalline Silicon Dioxide (SiO2)
Gneiss
Foliated Metamorphic Gneiss
Tiger's Eye (Rough)
Pseudomorph of Quartz after Crocidolite (SiO2 with FeOOH inclusions)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Gneiss
Gneiss
Baltic Amber (Butterscotch or Egg Yolk Variety)
Succinite (chemical formula: C10H16O)
Sandstone
Sandstone (SiO2 predominant)
Sandstone (specifically Arkose or Ferruginous Sandstone)
Sandstone (SiO2 predominant)
Sandstone Concretion
Clastic Sedimentary Concretion (primarily SiO2 with Fe2O3 cement)
Gneiss
Gneiss
Gneiss
Gneissic Metamorphic Rock
Petrified Wood
Silicified Wood (SiO2)
Ferruginous Sandstone (Gozzan-like)
Ferruginous Sandstone (SiO2 with FeO(OH) inclusions)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Sandstone (with potential Arkose/Lithic characteristics)
Arenite (Sedimentary rock composed of sand-sized grains)
Quartz (in a rock matrix)
Quartz (SiO2)
Red Sandstone Pebble
SiO2 with Fe2O3 (Quartz sandstone with hematite coating)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Banded Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Gneiss
High-grade metamorphic rock (Gneiss)
Chert (with Limonite staining)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Gneiss
Gneiss
Banded Iron Formation (BIF)
Banded Iron Formation (Fe2O3 + SiO2)
Gneiss
Gneiss
Gneiss (Metamorphic Rock)
Gneiss (high-grade regional metamorphic rock)
Chalcedony (Common Opal or Agate variant)
Silicon Dioxide (SiO₂)
Sodalite
Sodalite (Na8Al6Si6O24Cl2)
Gneiss
Gneiss
Banded Gneiss
Gneiss
Chert (Arrowhead Fragment)
Cryptocrystalline quartz (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Flint
Sedimentary cryptocrystalline quartz (SiO2)
Muscovite Mica (with Schist)
Muscovite - KAl2(AlSi3O10)(OH)2