Petrified Wood
Silicon Dioxide (SiO2)
Category
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Petrified Wood
Silicon Dioxide (SiO2)
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with iron oxide and other mineral impurities
Geode (Unopened)
Silica-rich concretion (SiO2)
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety often found as a river rock)
Chert (Green variety)
Silicon Dioxide (SiO2)
Chert (Yellow Jasper/Flint)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Red Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (and Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Quartzite variety)
Microcrystalline Silica (SiO2)
Chert Pebble Map
Microcrystalline Quartz (SiO2)
Fossil Shark Tooth
Selachii (fossilized dentition)
Chert (and Flint variant)
Chert (SiO2)
Green Chert
Microcrystalline Quartz (SiO2)
Limestone (Fossiliferous)
Calcium Carbonate (CaCO3)
Amber (Raw)
Succinite (Fossilized Resin)
Chert (and its variety Flint)
Silicon dioxide (SiO2) / Microcrystalline quartz
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline quartz (SiO2)
Coral Fossil (Petrified Coral)
Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Petrified Wood
Silicified Wood (SiO2)
Amber
Fossilized Tree Resin
Chert (Jasper/Agate)
Silicon Dioxide (SiO2)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Concretion
Septarian or Siderite Concretion
Chert (specifically Flint or Jasper variant)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Limestone
Calcium Carbonate (CaCO3)
Quartz Geode
Silicon Dioxide (SiO2)
Limestone with Stylolites
Calcareous sedimentary rock (CaCO3)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Starfish Fossil
Asteroidea fossil
Shungite
Non-crystalline carbon (similar to anthracite coal or meta-anthracite)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Chert / Flint
Chert (Microcrystalline Quartz, SiO2)
Chert (variations include Flint or Jasper)
Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (White-Tan variety)
Silicon dioxide (SiO2) / Microcrystalline Quartz
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Chert (SiO2)