Mineral (Chalcedony)

Brown chalcedony (possibly carnelian)

Microcrystalline quartz, SiO₂; carnelian is orange-red chalcedony

Dyed Agate

Silicon dioxide, SiO2

Chalcedony (possibly agate or common quartz)

Microcrystalline quartz, SiO₂

Carnelian

Carnelian (SiO2 with Iron oxide impurities)

Likely tumbled quartz/chalcedony pebble

Quartz (SiO₂), possibly microcrystalline chalcedony

Jasper-Agate

Silicon Dioxide (SiO2)

Agate Nodule (Chalcedony)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Agate (Dyed Blue)

SiO2 (Silicon Dioxide)

Geode Nodule Fragment

Quartz / Chalcedony Nodule

Sphalerite in Chalcedony (Crescent Carving)

Zinc Sulfide (ZnS) with Silicon Dioxide (SiO2)

Tumbled brown agate or jasper

Microcrystalline quartz, SiO₂ (likely chalcedony/agate with iron oxides)

Polished blue chalcedony (possibly agate)

Microcrystalline quartz, SiO₂; chalcedony, potentially banded agate

Chalcedony (Agate)

Chalcedony (Cryptocrystalline Quartz, SiO2)

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Chalcedony nodule (likely agate)

Microcrystalline quartz, SiO₂; banded varieties are agate

Tumbled yellow-orange chalcedony (likely carnelian)

Microcrystalline quartz, SiO₂; iron-bearing variety commonly called carnelian

Tumbled pale-yellow chalcedony (possibly yellow jasper)

Microcrystalline quartz, SiO₂; chalcedony/jasper varieties

Flower Agate

Silicon Dioxide (SiO2) with Chalcedony inclusions

Chalcedony (Agate/Carnelian variant)

Silicon Dioxide (SiO2)

Chalcedony (likely yellow agate or jasper fragment)

Microcrystalline quartz, SiO₂

Orange-pink chalcedony (likely carnelian/chalcedony rough)

Microcrystalline quartz, SiO₂; iron-oxide-bearing chalcedony

Tumbled jasper or chert

Microcrystalline quartz (SiO₂), likely iron-stained jasper/chalcedony

Chalcedony (Agate / Chert)

Silicon Dioxide (SiO2)

Chalcedony

Chalcedony (SiO2)

Possible rough agate/chalcedony nodule

Microcrystalline quartz (SiO₂), likely chalcedony or agate

White Chalcedony (likely Common Opal or Milky Quartz)

Silicon Dioxide (SiO2)

Tumbled blue chalcedony or dyed quartz

Microcrystalline quartz, SiO₂ (likely dyed chalcedony)

Chalcedony (Tumbled)

Cryptocrystalline Quartz (SiO2)

Chalcedony (Agate/Common Opal blend)

Microcrystalline Quartz (SiO2)

Chalcedony (Quartz Var.)

Silicon Dioxide (SiO2)

Brecciated Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Tumbled yellow chalcedony (likely yellow agate)

Chalcedony, microcrystalline quartz (SiO₂); possibly iron-stained agate

Red Jasper or Iron-stained Quartz

SiO2 with Fe impurities

Polished agate geode slice

Agate, a banded variety of microcrystalline quartz (SiO₂); likely quartz/chalcedony lining a geode

Blue Chalcedony

Silicon Dioxide (SiO2)

Botryoidal Chalcedony (Agate/Chert Nodule)

Chalcedony (SiO2)

Flower Agate (Plume Agate)

Chalcedony (Silicon Dioxide) with Spherulitic Inclusions - SiO2

Brown chalcedony (likely carnelian/agate)

Microcrystalline quartz, SiO₂; chalcedony variety

Chalcedony

Chalcedony (SiO2)

Tumbled orange-and-white chalcedony

Chalcedony, microcrystalline quartz (SiO₂), likely orange carnelian/white agate variety

Chalcedony (Agate/Carnelian)

Silicon Dioxide (SiO2)

Chalcedony (Agate/Carnelian)

Cryptocrystalline Silicon Dioxide (SiO2)