Asphalt aggregate
Human-made bituminous asphalt containing crushed silicate rock aggregate
Category
Browse organic (biological specimen) specimens identified by the Rock Identifier community.
Asphalt aggregate
Human-made bituminous asphalt containing crushed silicate rock aggregate
Pearl strand
Nacreous pearl, primarily aragonite (CaCO₃) with conchiolin protein
Chert / Flint (with Crinoid Stem Molds)
Microcrystalline Quartz (SiO2)
Fluorite
Calcium Fluoride (CaF2)
Flint in Limestone (Chert Nodule)
Sedimentary rock containing microcrystalline quartz (SiO2) within a carbonate matrix
Concretion
Septarian Concretion (Fragmentary)
Chert (Arrowhead Preform)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Quartzite river stone
Quartzite (SiO2)
Sandstone Pebble
Arenite (primarily SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Garnet
Almandine-Pyrope group, X3Y2(SiO4)3
Chert
Microcrystalline Quartz (SiO2)
Chert (often called Flint or Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Limestone Pebble with Crinoid Fossil
Calcium Carbonate (CaCO3) - Fossiliferous Limestone
Brachiopod Fossil in Limestone
Phylum Brachiopoda embedded in sedimentary rock
Fossil Shark Tooth
Carcharocles or Lamniformes (order)
Chert
Microcrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Chert (or Fossiliferous Limestone)
Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert / River Jasper
Silicon Dioxide (SiO2)
Chert (Jasper transition)
Microcrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (containing Iron Oxide spots)
Microcrystalline Quartz (SiO2)
Chert (Pebble)
Chert (Microcrystalline Quartz, SiO2)
Chert / Flint
Silicon Dioxide (SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Fossilized Dinosaur Skull (Tyrannosaurus rex)
Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica
Green Chert (Jasper)
Silicon Dioxide (SiO2)
Chert (Jasper/River Stone)
Silicon dioxide (SiO2) - Microcrystalline quartz
Chert (River Siltstone/Quartzite)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (Smooth River Pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (often called Flint in this context)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Moss Agate
Chalcedony (SiO2 with inclusions)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Honeycomb Coral Fossil
Favosites (extinct genus of tabulate coral)