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

Banded agate (polished agate slice)

Agate, a variety of microcrystalline quartz (SiO₂; chalcedony)

Polished carnelian (likely)

Carnelian, a reddish-orange cryptocrystalline quartz variety; SiO₂

Iron-stained jasper/chert fragment

Microcrystalline quartz (SiO₂), likely hematite/goethite-bearing jasper

Tumbled agate or chalcedony (probable)

Microcrystalline quartz, SiO₂

Red jasper (likely iron-rich chert)

Microcrystalline quartz, SiO₂, colored mainly by hematite/goethite

Chert (or Chalcedony)

Microcrystalline Quartz (SiO2)

Tumbled pale-yellow chalcedony (possibly yellow jasper)

Microcrystalline quartz, SiO₂; chalcedony/jasper varieties

Picture Jasper

SiO2, Microcrystalline Quartz

Tumbled amber-colored agate or chalcedony

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

Yellow chalcedony or quartz fragment

Microcrystalline quartz, SiO₂ (tentative; possibly iron-stained chalcedony)

Gravel or Pebble

Clastic Sedimentary Grain (typically composed of Quartz or Silicate minerals)

Yellow Jasper

SiO2 (Silicon Dioxide)

Red/orange chalcedony (carnelian), possibly dyed or heat-treated

Chalcedony, cryptocrystalline SiO₂ (quartz variety)

Tumbled brown stone, likely jasper or chert

Microcrystalline quartz (SiO₂), probably iron-stained jasper/chert

Carnelian

Orange chalcedony, microcrystalline quartz (SiO₂)

Agate

Chalcedony (cryptocrystalline variety of Quartz, SiO2)

Chert (Jasper variety)

Microcrystalline Quartz (SiO2)

Polished chrysoprase (likely)

Chalcedony, microcrystalline quartz (SiO₂), colored by nickel-bearing minerals

Red jasper (possible polished or dyed stone)

Jasper, an opaque microcrystalline variety of quartz (SiO₂)

Orange chalcedony or tumbled carnelian fragment

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

Red Jasper

Jasper (Silica/Microcrystalline Quartz with Hematite inclusions), SiO2

Quartz (chalcedony variety) or Limestone with Quartz Veins

SiO2 (for Quartz/Chalcedony); CaCO3 (for Limestone)

Jasper with Quartz Veining

Silicon Dioxide (SiO2) with impurities

Light-colored agate (likely chalcedony)

Chalcedony, microcrystalline quartz (SiO₂); exact variety is uncertain from the image

Brown chalcedony (likely carnelian)

Chalcedony, microcrystalline quartz (SiO₂); iron-stained brown variety

Tumbled brown jasper (likely brecciated jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide and other mineral inclusions

Tumbled jasper

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

Polished blue-gray agate/geode slice (tentative)

Microcrystalline quartz (chalcedony), SiO₂, possibly with druzy quartz

Chalcedony nodule (likely agate)

Microcrystalline quartz, SiO₂; banded varieties are agate

Red jasper (polished/cut rough)

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

Chert (Iron-stained)

Chert (Microcrystalline Quartz, SiO2)

Tumbled jasper (likely brecciated or red jasper)

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

Tumbled jasper (likely brecciated or ocean jasper)

Microcrystalline quartz (SiO₂), with iron-oxide staining and possible chalcedony

Red Jasper (beads)

Silicon Dioxide (SiO2) with iron inclusions

Agate (chalcedony), likely a cut nodule

Agate, a banded variety of microcrystalline quartz (SiO₂); associated iron oxides stain the rough outer matrix.

Jasper

Silicon dioxide (SiO2) with impurities

Polished brecciated jasper

Jasper, microcrystalline quartz (SiO₂), with iron oxides and pale chalcedony/quartz veins

Polished banded agate

Agate, a banded variety of microcrystalline quartz (SiO₂)

Small tumbled quartz pebble, possibly chalcedony

Quartz (SiO₂), likely microcrystalline chalcedony

Red jasper (likely tumbled)

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

Polished orbicular agate (likely ocean jasper)

Microcrystalline quartz, SiO₂; chalcedony with orbicular patterns and possible mineral inclusions

Imperial Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz with Mineral Inclusions