Mineral (Specifically A Variety Of Chalcedony, Which Is A Cryptocrystalline Quartz)

Polished jasper pebble

Microcrystalline quartz (chalcedony), usually with iron-oxide impurities

Red jasper pebble

Microcrystalline quartz (SiO₂), colored by iron oxides; possibly brecciated jasper

Polished carnelian (likely brecciated agate) heart

Microcrystalline quartz, SiO₂; chalcedony with iron-oxide coloration

Strawberry Quartz

Quartz (SiO2) with inclusions of Goethite or Hematite

Quartz (Milky/Chalcedony variety)

Silicon Dioxide (SiO2)

Yellow Jasper

Chalcedony (SiO2 with iron oxide inclusions)

Chalcedony Nodule (Agate/Chert)

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

Flint Pebble

Sedimentary cryptocrystalline quartz (SiO2)

Polished banded agate heart

Microcrystalline quartz (SiO₂), primarily chalcedony with iron-oxide inclusions

Polished banded agate (likely blue lace agate)

Chalcedony, microcrystalline SiO₂, with iron and other trace-element impurities

Jasper (brecciated or orbicular jasper)

Microcrystalline quartz/chalcedony (SiO₂), colored by iron oxides and other impurities

Chalcedony (Botryoidal or Tumbled)

Chalcedony (SiO₂)

Agate

Cryptocrystalline Silicon Dioxide (SiO2)

Fancy Jasper

Cryptocrystalline Quartz (SiO2) with iron oxide inclusions

Blue Chalcedony Cube

Silicon Dioxide (SiO2)

Chert (specifically varieties like Chalcedony or Flint)

Silicon Dioxide (SiO2)

Yellow chalcedony (likely tumbled quartz)

Chalcedony, cryptocrystalline SiO₂; possibly iron-stained quartz or yellow jasper

Tumbled orange chalcedony (likely carnelian)

Cryptocrystalline quartz, SiO₂; carnelian is orange-red chalcedony colored mainly by iron oxides

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)

Tumbled chalcedony (likely yellow/brown agate or carnelian)

Microcrystalline quartz, SiO₂; chalcedony with possible iron-oxide staining

Tumbled agate or chalcedony

Microcrystalline quartz (SiO₂), likely brown/orange chalcedony or agate

Tumbled brown agate/chalcedony (probable)

Microcrystalline quartz, SiO₂; likely iron-stained agate or jasper

Red jasper (likely tumbled or naturally worn)

Jasper, microcrystalline quartz/chalcedony (SiO₂), colored mainly by iron oxides

Chalcedony

Chalcedony (SiO2)

Polished pink agate/chalcedony pebble

Chalcedony (microcrystalline quartz, SiO₂), likely iron-stained agate

Chalcedony (Agate/Carnelian variant)

Silicon Dioxide (SiO2)

Agate

Silicon dioxide (SiO2) - variety Chalcedony

Tumbled jasper

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and other mineral impurities

Picture Jasper

SiO2

Polished red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides

Jasper with Iron Oxides

Silicon Dioxide (SiO2) with Fe2O3 inclusions

Agate (Chalcedony Variation)

Silicon Dioxide (SiO2)

Quartz (specifically Milky/White Quartz)

Silicon Dioxide (SiO2)

Tumbled jasper or chalcedony pebble

Microcrystalline quartz, SiO₂ (likely jasper/chalcedony)

Red cabochon gemstone, likely carnelian or red agate

Cryptocrystalline quartz (chalcedony), SiO₂

Polished brown chalcedony or jasper

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

Banded Chalcedony (Agate)

Cryptocrystalline Quartz (SiO2)

Polished red jasper and carnelian-like stones

Jasper: microcrystalline quartz (SiO₂), commonly colored by iron oxides; translucent piece may be carnelian, a chalcedony variety

Yellow Jasper

Silicon Dioxide (SiO2) with Goethite inclusions

Tumbled carnelian (orange chalcedony)

Carnelian, a microcrystalline variety of quartz (SiO₂), commonly colored by iron oxides

Agate and Chalcedony Assortment

Silicon Dioxide (SiO2)

Polished carnelian/chalcedony

Microcrystalline quartz (SiO₂), iron-oxide-colored chalcedony