Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2 - Silicon Dioxide)
Category
Browse sedimentary (cryptocrystalline quartz) specimens identified by the Rock Identifier community.
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2 - Silicon Dioxide)
Banded Agate (specifically Botryoidal/Orbicular Agate)
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Moss Agate
Silicon dioxide (SiO2) with inclusions of hornblende or chlorite
Chert (Jasper/Opaline variety)
Silicon Dioxide (SiO2)
Milky Quartz / Rose Quartz fragment
Silicon Dioxide (SiO2)
Ocean Jasper
Orbicular Jasper (Silicon Dioxide with impurities), SiO2
Chrysoprase
Silicon dioxide with nickel impurities (SiO2 + Ni)
Argetine Blue Agate (Chalcendony variant)
Silicon Dioxide (SiO₂)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky or Iron-Stained Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz
Silicon dioxide (SiO2)
Chrysoprase
Chrysoprase (a variety of Chalcedony, SiO₂)
Chert or Flint (polished/water-worn)
Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.
Clear Quartz
Silicon Dioxide (SiO2)
Bloodstone
Heliotrope (a variety of Chalcedony, SiO₂ with inclusions)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Petrified Wood
Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Blue Quartz (Aventurine)
Silicon Dioxide (SiO2) with Crocidolite or Magnesio-riebeckite inclusions
Blue Lace Agate (Tumbled)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Limonite (Ironstone)
Hydrated Iron Oxide (FeO(OH)·nH2O)
Pyrite on Quartz
Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)
Fluorite with Quartz coating
Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)
Quartz (Pale Rose or Milky Variety)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Geode (Unopened)
Siliceous Geode (SiO2)
Chrysoprase (Nickel-bearing Chalcedony)
Silicon Dioxide (SiO2) with traces of Hydrous Nickel Silicates
Agate (Lace Agate Geode Slice)
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO₂)
Green Aventurine
Aventurine (variety of Quartz - SiO2)
Flint / Chert
Silicon dioxide (SiO2)
Quartz (Milky or Common Quartz)
Silicon Dioxide (SiO2)
Agate
Silicon Dioxide (SiO2) - Banded Chalcedony
Quartz
Quartz (SiO2 - Silicon Dioxide)
Chrysocolla
Hydrated copper phyllosilicate, Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)