Blue chalcedony cabochon (probable)
Chalcedony, cryptocrystalline quartz; silicon dioxide (SiO₂)
Category
Browse mineraloid (cryptocrystalline quartz) specimens identified by the Rock Identifier community.
Blue chalcedony cabochon (probable)
Chalcedony, cryptocrystalline quartz; silicon dioxide (SiO₂)
Agate
SiO2 (Silicon Dioxide)
Chalcedony (Agate / Quartz Nodule)
Silicon Dioxide (SiO2)
Carnelian (Yellow-Orange Chalcedony)
Silicon Dioxide (SiO2) with iron oxide inclusions
Pink Mimbres Agate / Plume Agate
Silicon dioxide (SiO2) with mineral inclusions
Petrified Wood
Silicified wood (SiO2)
Chert (Jasper variation)
Silicon Dioxide (SiO2)
Chert (Jasper/Flint variety)
Silicon dioxide (SiO2)
Carved Stone Turtle
Carved Soapstone and Quartz
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
Yellow Quartzite (or Yellow Chalcedony Pebble)
Silicon Dioxide (SiO2)
Pale pink chalcedony bangle
Chalcedony (microcrystalline quartz, SiO₂), likely pink chalcedony or dyed/treated material
Leopardite
Quartz porphyry / Quartz monzonite with manganese oxide spots
Chert (or Cryptocrystalline Quartz)
Silicon Dioxide (SiO2)
Banded Chert
Sedimentary Cryptocrystalline Quartz (SiO2)
Carnelian
SiO2 (Silicon Dioxide)
Carnelian
Silicon dioxide (SiO2) with iron oxide impurities
Shiva Lingam
Cryptocrystalline Quartz (Jasproid/Chalcedony mix)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Vein in Basalt
Silica-infilled basaltic host rock
Chert (often called Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline or cryptocrystalline Quartz (SiO2)
Chert (and Chert Flake)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Polished agate slice
Agate, a banded variety of chalcedony (microcrystalline SiO₂)
Tumbled brown quartz/chalcedony (probable)
Quartz, SiO₂; possibly brown chalcedony or jasper
Quartz-veined Basalt or Diabase Pebble
Igneous rock with hydrothermal quartz vein
Carved Sea Turtle Figurine (Aventurine / Quartz / Jasper)
Quartz variety (SiO2) / Polycrystalline Quartz Aggregate
Geode (unopened)
Quartz-filled Geode (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Flint
SiO2 (Cryptocrystalline Quartz / Chert)
Chert / Flint (Brecciated or Fossiliferous Limestone with Silicification)
Sedimentary cryptocrystalline quartz (SiO2)
Flint
SiO2 (Cryptocrystalline Quartz / Chert)
Flint
Sedimentary cryptocrystalline quartz (SiO2)
Flint
SiO2 (Cryptocrystalline Quartz / Chert)
Flint
Sedimentary cryptocrystalline quartz (SiO2)
Flint / Chert Nodule
Sedimentary cryptocrystalline quartz (SiO2)
Chert (Siliceous Pebble)
Microcrystalline / Cryptocrystalline Quartz (SiO2)
Shiva Lingam
Cryptocrystalline Quartz and Iron Oxide
Chert (often called Flint or Jasper)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Carnelian
Carnelian (Cryptocrystalline Quartz, SiO2)
Red Jasper (Beach Pebble)
Jasper (Cryptocrystalline Quartz, SiO2)
Chert Concretion
Sedimentary Cryptocrystalline Quartz (SiO2)