Petrified Wood
Silicified wood (SiO2)
Category
Browse organic mineraloid specimens identified by the Rock Identifier community.
Petrified Wood
Silicified wood (SiO2)
Shark Tooth Fossil
Otodus sp. (possibly Cretalamna)
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Pearl (with Peridot)
Calcium carbonate (CaCO3) + Conchiolin; Peridot: Magnesium iron silicate (Mg, Fe)2SiO4
Banded Chert (or River Jasper)
Microcrystalline Quartz (SiO2) with iron oxide impurities
Red Jasper
Jasper (Silicon Dioxide with Iron inclusions - SiO2)
Chert (Brown variety / Common Jasper)
Microcrystalline Quartz (SiO2)
Chert (variously identified as Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Field Stone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Anthracite Coal
Anthracite
Septarian Nodule (Thunder Egg)
Septarian Concretion (CaCO3 + CaMg(CO3)2 + SiO2)
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (Tan/Grey variety)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Limestone-hosted Pebble)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (often called Flint or Jasper locally)
Chert (Microcrystalline Quartz, Formula: SiO2)
Petrified Wood
Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)
Mookaite Jasper
Silicified Radiolarite (SiO2)
Banded sandstone pebble
Quartz-rich lithic sandstone; exact provenance and composition require testing
Jasper
Silicon Dioxide (Microcrystalline Quartz / Chalcedony)
Petrified Wood
Silicified wood (Quartz replacement)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood / Fossilized Wood
Silicified Wood (Silicon Dioxide - SiO2)
Chert (often called Flint when found in chalk/limestone)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Smooth River Stone)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2 permineralization)
Petrified Wood
Silicified Wood (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite impurities
Quartz Geode
Silicon Dioxide (SiO2)
Coral Fossil (Petrified Coral)
Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)
Jasper (specifically Yellow Jasper and Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
Chert (Weathered)
Chert (Microcrystalline Quartz, SiO2)
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Banded Chert (with Quartz Vein)
Microcrystalline Silica (SiO2)
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Limestone with Quartz/Calcite Veins
Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)
Petrified Wood
Silicified Wood (primarily SiO2)