Chert (Jasper/Common Opal mix)
Microcrystalline Quartz (SiO2)
Category
Browse organic material (likely a fruit or berry) specimens identified by the Rock Identifier community.
Chert (Jasper/Common Opal mix)
Microcrystalline Quartz (SiO2)
Fossil Coral (Rugose Coral Fragment)
Rugosa (extinct order of solitary and colonial corals)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of organic matter)
Chert (often called Flint or Jasper)
Microcrystalline quartz (SiO2)
Chert (specifically Green Chert/Jasper)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Jasper/Flint variety)
Microcrystalline silicon dioxide (SiO2)
Chert (Jasper-bearing)
Chert (Silicon Dioxide, SiO2)
Coal (likely Bituminous or Lignite)
Organic Sedimentary Rock (Carbonaceous)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Chalcedony)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (Field Stone)
Chert (Silicon Dioxide, SiO2)
Chert Pebble (with fossil shell fragment)
Microcrystalline Quartz (SiO2) with Calcified Invertebrate Impression
Petrified Wood
Silicified Wood (primarily SiO2)
Tumbled yellow-brown stone, likely quartzite or chalcedony
Quartz-rich rock; predominantly microcrystalline quartz (SiO₂), identification uncertain from image alone
Chert (Jasper)
Microcrystalline Quartz (SiO2) with Iron Oxide inclusions
Chert (Iron-rich or Slate-like variant)
Silicon Dioxide (SiO2)
Fossilized Shark Tooth
Eocene Lamniformes (Mackerel Shark clade)
Weathered mica-rich schist
Muscovite–biotite schist, possibly quartz-bearing
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Tan/Brown)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (Jasper/Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (variations include Flint or Jasper)
Aphanitic Silica (SiO2)
Beaded Jewelry (Assorted Gemstones)
Various minerals, including but not limited to Quartz (SiO2), Garnet (X3Y2(SiO4)3), Jade (Na(Al,Fe)Si2O6), Amethyst (SiO2),等の多様な組み合わせ
Chert (variations like Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (SiO2)
Sandstone with Vitrinite/Coal inclusions
Arenite with Carbonaceous inclusions
Amber
Succinite (specifically for Baltic Amber), Formula: C10H16O
Moss Agate
Chalcedony (Silicon Dioxide - SiO2) with inclusions
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
Chert (Flint Nodules)
Chert (Microcrystalline Quartz, SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
Sandstone
Sandstone (principally SiO2/Silicon Dioxide)
Vuggy Limestone
Calcium Carbonate (CaCO3) with Quartz/Calcite inclusions
Petrified Wood
Silicified Wood (Permineralized Lycopsid, Conifer, or Hardwood)
Mosasaur Tooth
Mosasaurus sp.
Petrified Wood
Silicified Wood (SiO2 permineralization)
Chert (Iron-stained)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (mainly Quartz / SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Jasper
Microcrystalline Quartz (SiO2)