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

Tumbled red jasper (probable)

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

Jasper with Quartz Vein

Microcrystalline quartz (SiO2) and chalcedony with a quartz vein

Chert (or possibly Flint)

SiO2 (Silicon Dioxide)

Tumbled banded blue agate

Chalcedony (microcrystalline quartz, SiO₂), variety agate

Polished chrysoprase (likely)

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

Blue Lace Agate

Silicon Dioxide (SiO₂), a variety of Chalcedony

Yellow Jasper

Cryptocrystalline Quartz (SiO2)

Polished agate pendant (likely carnelian or plume agate)

Microcrystalline quartz, SiO₂ (chalcedony); exact variety cannot be confirmed from the image

Red jasper

Jasper, microcrystalline quartz (SiO₂) with iron-oxide impurities

Brown chalcedony/agatic jasper nodule

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony with included or weathered host material

Polished carnelian

Cryptocrystalline chalcedony (SiO₂), orange-red variety colored mainly by iron oxides

Carnelian (orange chalcedony)

Chalcedony, microcrystalline quartz (SiO₂), iron-colored variety

Quartz Geode Fragment

Crystalline Silicon Dioxide (SiO2)

Polished multicolored jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), likely iron- and manganese-stained chert

Blue Chalcedony

Silicon Dioxide (SiO2)

Tumbled brown jasper

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

Chert (Jasper variety)

Microcrystalline Quartz (SiO2)

Chert (specifically Flint or Dark Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz (Chert/Chalcedony Variety)

Silicon Dioxide (SiO2)

Tumbled brown chalcedony (likely carnelian or jasper)

Microcrystalline quartz, SiO₂ (chalcedony variety)

Yellow jasper (likely polished/tumbled)

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

Jasper

Jasper (Silicon Dioxide, SiO2)

Tumbled chalcedony (likely carnelian or jasper)

Microcrystalline quartz, SiO₂; reddish varieties are carnelian, while more opaque material may be jasper

Chert (or Chalcedony)

Microcrystalline Quartz (SiO2)

Quartz (Milky or Cloudy)

Silicon Dioxide (SiO2)

Polished carnelian agate

Microcrystalline quartz (SiO₂), chalcedony with iron-oxide coloration

Agate

Silicon dioxide (SiO2)

Likely banded agate pebble

Microcrystalline quartz (chalcedony), SiO₂

Carnelian pendant

Carnelian, orange chalcedony (microcrystalline quartz, SiO₂)

Orange carnelian (likely tumbled chalcedony)

Cryptocrystalline quartz, SiO₂; orange color commonly from iron oxides

Tumbled banded agate

Chalcedony (microcrystalline quartz), SiO₂

Thunderegg (specifically a Jasper/Agate-filled Geode nodule)

Silicon Dioxide (SiO2) within Rhyolitic Matrix

Chalcedony (Yellow Chert / Agate)

Quartz (Silicon Dioxide - SiO2)

Yellow chalcedony (likely lemon quartz or citrine)

Cryptocrystalline silica, SiO₂; possible quartz variety

Polished brecciated jasper

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

Tumbled carnelian/chalcedony

Cryptocrystalline quartz (SiO₂), likely iron-stained chalcedony

Polished amber agate pendant/beads

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

Orbicular jasper (likely ocean jasper)

Silica-rich microcrystalline quartz/chalcedony with iron-oxide and other mineral inclusions; commonly classified as orbicular jasper

Chert (specifically Novaculite)

Microcrystalline Quartz (SiO2)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Reddish-brown chert or jasper fragment

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

Dyed Agate Slice

Chalcedony (Silicon Dioxide, SiO2) with artificial pigment