Mineral (Chalcedony)

Tumbled white chalcedony (likely milky quartz)

Chalcedony, microcrystalline quartz (SiO₂)

Carnelian (red-orange chalcedony)

Chalcedony, cryptocrystalline SiO₂; quartz-group mineral

Chalcedony (rough)

Microcrystalline quartz, SiO₂; likely gray chalcedony with iron-oxide staining

Tumbled jasper (likely picture/brecciated jasper)

Microcrystalline quartz (chalcedony), SiO₂, colored by iron oxides

Polished jasper carving or slab

Jasper, an opaque microcrystalline variety of quartz (SiO₂), likely iron-oxide-rich brecciated or orbicular jasper

Carnelian (Chalcedony)

Silicon Dioxide (SiO2)

Tumbled agate (likely chalcedony)

Microcrystalline quartz, SiO₂; agate is banded chalcedony, though banding is not clear in this specimen

Pink Chalcedony (Agate/Jasper blend)

Silicon Dioxide (SiO₂)

Polished banded agate

Agate, a banded variety of microcrystalline quartz (SiO₂)

Geode

Quartz / Chalcedony nodule with mineralized cavity

Chalcedony nodule (possibly agate)

Microcrystalline quartz, SiO₂; potentially banded agate

Dalmatian jasper (polished stone beads)

Commercial “Dalmatian jasper”; typically a feldspar-rich rock with dark aegirine or arfvedsonite inclusions, not true jasper

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Tumbled chalcedony or quartz fragment

Microcrystalline quartz, SiO₂ (probable chalcedony)

Tumbled chalcedony (likely jasper/chert variety)

Microcrystalline quartz, SiO₂ (chalcedony; opaque varieties commonly called jasper or chert)

Grey Chalcedony

Silicon Dioxide (SiO2)

Chalcedony / Agate

Silicon Dioxide (SiO2)

Yellow Chalcedony

Cryptocrystalline Quartz (SiO2)

Tumbled Agate

Silicon Dioxide (SiO2)

Blue Chalcedony

Silicon Dioxide (SiO2)

Green Chalcedony (Batu Akik)

Silicon Dioxide (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron inclusions

Likely banded agate pebble

Microcrystalline quartz (chalcedony), SiO₂

Polished brecciated jasper

Microcrystalline quartz (SiO₂), likely iron-oxide-rich jasper

Polished brecciated jasper (likely picture jasper)

Silica-rich microcrystalline quartz/chalcedony, SiO₂, with iron-oxide and clay inclusions

Polished orbicular jasper

Microcrystalline quartz (SiO₂) with iron-rich and altered volcanic inclusions

Tumbled carnelian

Carnelian, orange chalcedony (microcrystalline SiO₂)

Jasper (Iron-stained Quartzite/Chert)

Silicon Dioxide (SiO2) with iron oxide inclusions

Carnelian (Chalcedony)

SiO2 (Silicon Dioxide with iron oxide inclusions)

Chalcedony on Matrix

Silicon Dioxide (SiO2)

Yellow Chalcedony / Carnelian

Silicon Dioxide (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Blue Chalcedony

Silicon Dioxide (SiO2)

Dendritic Agate or Merlinite (Polished Cabochon)

Silicon dioxide with manganese or iron oxide inclusions (SiO2)

Carnelian (Agate)

SiO2 (Silicon Dioxide with Iron Oxide inclusions)

Polished banded agate (likely laguna-style fortification agate)

Microcrystalline quartz, SiO₂; chalcedony with concentric bands

Chalcedony with jasper (likely brecciated jasper)

Microcrystalline quartz, SiO₂, with iron-oxide-rich jasper fragments

Botryoidal chalcedony (agate/quartz geode fragment)

Microcrystalline quartz, SiO₂, likely chalcedony with drusy quartz and iron-oxide staining

Rounded quartz-rich pebble

Likely microcrystalline quartz (chalcedony), possibly weathered quartzite

Chalcedony (River or Beach Pebbles)

Chalcedony (Silicon Dioxide, SiO2)

Chalcedony (Common Opal variant)

Silicon dioxide (SiO2) with microcrystalline structure

Polished agate pebble

Banded chalcedony, a microcrystalline variety of quartz (SiO₂)