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

Polished orbicular jasper (likely ocean jasper)

Silicified microcrystalline quartz (SiO₂), with iron-oxide and other mineral inclusions; exact variety cannot be confirmed from the image

Chalcedony (specifically Blue Chalcedony or Common Opal variety)

Silicon Dioxide (SiO₂)

Brown chalcedony (likely carnelian/agate)

Microcrystalline quartz, SiO₂; chalcedony variety

Iron-rich jasper (likely rough jasper/chert)

Microcrystalline quartz (SiO₂), colored by iron oxides

Chalcedony (specifically Agate or Carnelian variety)

Cryptocrystalline Silica (SiO2)

Jasper

SiO2 (Silicon Dioxide)

Smoky Quartz

Silicon Dioxide (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

Banded Agate (specifically Carnelian Agate slice)

Chalcedony (cryptocrystalline variety of Quartz), SiO2

Carnelian Agate/Jasper blend

Silicon Dioxide (SiO2) - variety of Chalcedony

Blue Chalcedony (Blue Lace Agate variety)

Silicon Dioxide (SiO₂)

Flint

Silicon dioxide (Microcrystalline Quartz / Chert)

Ocean Jasper

Spherulitic Chalcedony (SiO2)

Agate (Carnelian / Chalcedony)

Silicon Dioxide (SiO2)

Polished banded agate (likely petrified wood)

Microcrystalline quartz (SiO₂); possibly silicified wood

Red jasper (likely)

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

Quartz Pebble (Chert/Chalcedony)

Silicon Dioxide (SiO2)

Small reddish-brown pebble, possibly jasper or iron-stained quartz

Unidentified silica-rich pebble; visual identification is insufficient to distinguish jasper, quartz, or another material

Brecciated Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Jasper / Chert (river tumbled)

Microcrystalline Quartz (SiO2)

Blue Lace Agate

Chalcedony (Silicon Dioxide, SiO2)

Carnelian

SiO2 (Silicon Dioxide)

Blue Chalcedony

Silicon Dioxide (SiO2)

Banded Agate (specifically Carnelian Agate color)

Silicon Dioxide (SiO2) - variety of Chalcedony

Blue agate (likely dyed and polished)

Microcrystalline quartz, SiO₂ (chalcedony); blue color may be dye

Yellow jasper (likely polished/tumbled)

Microcrystalline quartz, SiO₂, colored by iron oxides; exact identification is uncertain from the image

Tumbled carnelian

Carnelian, orange-red chalcedony (microcrystalline SiO₂)

Jasper and Quartz Pebble

Silicon Dioxide (SiO2) microcrystalline quartz variety

Banded Agate (specifically Botswana Agate or Water-line Agate)

Chalcedony (cryptocrystalline variety of Quartz), SiO2

Smoky Quartz

Silicon Dioxide (SiO2)

Chalcedony

Silicon Dioxide (SiO2)

Strawberry Quartz

Quartz (SiO2) with inclusions of Goethite or Hematite

Red Jasper

Microcrystalline Quartz (SiO2) with iron oxide inclusions

Jasper

Silicon dioxide (SiO2)

Dyed Agate Slice

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Brecciated jasper

Jasper (microcrystalline quartz, SiO₂), likely iron-oxide-rich breccia

Ocean Jasper

Spherulitic Chalcedony (SiO2)

Polished yellow-orange chalcedony (likely carnelian)

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

Banded Agate (specifically Eye Agate / Chalcedony)

Agate (Cryptocrystalline variety of Quartz, SiO2)

Tumbled purple jasper (likely rhyolite-derived jasper)

Microcrystalline quartz (SiO₂) with iron/manganese oxide impurities; possibly purple rhyolitic jasper

Banded Agate (specifically Carnelian Agate)

Silicon dioxide (SiO2) - Chalcedony variety