Chert (Flint)
Microcrystalline Quartz (SiO2)
Category
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
Chert (Flint)
Microcrystalline Quartz (SiO2)
Tiger's Eye (often misinterpreted as Gold Ore in this context)
Pseudomorph of Quartz after Crocidolite (SiO2)
Chert (often called Jasper or Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Polished black stone, likely basalt or black jasper
Indeterminate; possible fine-grained basalt (plagioclase–pyroxene) or black jasper/microcrystalline quartz
Petrified Wood
Silicified Wood (SiO2)
Fossilized Shark Tooth (Megalodon or Carcharocles fragment)
Elasmobranchii (Fossilized tooth root / crown section)
Petrified Wood
Silicified Wood (SiO2)
Chert (likely flint), possibly chalcedony-rich
Microcrystalline quartz, SiO₂ (quartz/chalcedony)
Polished ocean jasper (orbicular jasper)
Microcrystalline quartz (SiO₂) with chalcedony, iron oxides, and assorted silicate inclusions
Druzy Chalcedony/Quartz on Fluorite core
Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)
Chert with Limestone Cortex
Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3)
Petrified Wood
Silicified Wood (primarily SiO2)
Fossil gastropod shell
Fossilized gastropod, likely a small marine snail; exact genus cannot be determined from the image
Polished granite or gneiss cobble
Banding of quartz, feldspar, mica, and ferromagnesian minerals; likely gneiss, possibly weathered granite
Banded Chert / Agate
Silicon Dioxide (SiO2)
Fossilized Bone Fragment
Vertebrate Fossil Material (Apatite/Calcium Phosphate)
Fossil Shell (Brachiopod or Mollusk)
Phylum Brachiopoda or Class Bivalvia (e.g., Mucrospirifer or similar genus)
Petrified Wood
Silicified wood (primarily SiO2)
Likely fossil oyster shell
Fossilized bivalve shell; exact species cannot be identified from the image
Chert (Flint)
Chert (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Polished ocean jasper (orbicular jasper)
Microcrystalline quartz/chalcedony with iron- and manganese-bearing inclusions; SiO₂
Petrified Wood
Silicified Wood (SiO2)
Chrysocolla in Chalcedony (Gem Silica)
Hydrated copper phyllosilicate and silicon dioxide (SiO2 with (Cu,Al)2H2Si2O5(OH)4)
Unidentified brown mineral/rock fragment
Indeterminate from image; possibly iron-stained quartz, feldspar, or weathered limonite
Petrified Wood
Silicified Wood / Xylopal
Flint (chert), likely brown flint
Microcrystalline quartz/chalcedony (SiO₂)
Tumbled ocean jasper (orbicular jasper), likely brecciated variety
Jasper: microcrystalline quartz (SiO₂) with iron-oxide staining and other silicate inclusions
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Tumbled serpentine-rich stone
Serpentinite, commonly dominated by antigorite, lizardite, or chrysotile
Limestone or Sandstone Cobble
Sedimentary rock (Calcium carbonate or Quartz based)
Petrified Wood
Silicified Wood (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Fossilized Shark Tooth or Bone Fragment
Vertebrate Fossil (likely Carcharodon or similar genus)
Jasper
Jasper (Silicon Dioxide, SiO2)
Otodus Shark Tooth
Otodus obliquus