Microcrystalline Quartz

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Tumbled brown chalcedony (likely jasper or chert)

Microcrystalline quartz, SiO₂; opaque varieties are commonly called jasper or chert

Polished carnelian (red-orange chalcedony)

Carnelian, a cryptocrystalline variety of quartz (SiO₂)

Polished orange chalcedony or carnelian

Cryptocrystalline quartz (SiO₂), likely carnelian

Agate Nodule (Chalcedony)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Lake Superior Agate

Silicon Dioxide (Chalcedony / Quartz, SiO2)

Weathered jasper pebble (probable red jasper/chert)

Microcrystalline quartz, SiO₂, colored mainly by iron oxides

Red Jasper

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

Melo Melo Pearl (or Golden Chalcedony / Yellow Jasper Sphere)

Non-nacreous calcium carbonate pearl (or SiO2 - Silicon Dioxide)

Likely jasper pebble

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

Agate Geode Node

Cryptocrystalline Quartz (SiO2)

Tumbled brown chalcedony or jasper

Microcrystalline quartz, SiO₂; possibly iron-bearing jasper

Banded Agate (specifically Eye Agate / Chalcedony)

Agate (Cryptocrystalline variety of Quartz, SiO2)

Weathered quartz-rich rock, possibly quartzite or chert

Quartz (SiO₂), likely in a quartzite matrix; exact identification is uncertain from the image

Likely chert or chalcedony

Microcrystalline quartz (SiO₂), possibly waxy chalcedony or chert

Tumbled orange chalcedony or carnelian

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

Agate

Silicon Dioxide (SiO2) - Chalcedony variety

Fossilized Gastropod Shell

Gastropoda (Fossilized internal mold or shell body)

Jasper

Jasper (Silicon Dioxide, SiO2)

Red Jasper

Microcrystalline quartz (SiO2) with Hematite (Fe2O3) impurities

Red Jasper

SiO2 (Silicon Dioxide with Iron Oxide inclusions)

Kambaba Jasper (Crocodile Jasper)

Fossilized Stromatolite (Cyanobacteria microfossils in silica Matrix)

Green Jasper

Silicon Dioxide (SiO2) with iron silicate inclusions

Jasper with Chalcedony

Silicon Dioxide (SiO2)

Agate

Chalcedony (SiO2)

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with Iron Oxides

Possible tumbled jasper or iron-rich chert

Microcrystalline quartz (SiO₂), commonly colored by iron oxides

Polished brecciated jasper

Jasper (microcrystalline quartz, SiO₂), brecciated variety

Botryoidal chalcedony/geode fragment

Chalcedony, microcrystalline quartz (SiO₂), likely iron-oxide coated

Tumbled pale-blue chalcedony (likely blue lace agate)

Microcrystalline quartz, SiO₂; chalcedony, possibly banded blue lace agate

Iron-stained quartz-rich rock, possibly jasper or chert

Microcrystalline quartz (SiO₂) with iron oxides/hydroxides

Polished brown jasper pebble

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

Tumbled amber-brown chalcedony (probable carnelian/ag ate)

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

Tumbled red jasper

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

Jasper (Green Jasper / Chert)

Silicon Dioxide (SiO2 with inclusions)

Tumbled jasper

Microcrystalline quartz (chalcedony), SiO₂; likely iron-stained jasper

Botryoidal chalcedony (possibly agate/geode material)

Microcrystalline quartz, SiO₂; commonly intergrown with calcite and iron oxides

Red jasper (iron-rich chert), possibly brecciated

Microcrystalline quartz/chalcedony (SiO₂) colored by hematite and goethite

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Black Onyx or Dyed Agate Node

Cryptocrystalline Quartz (SiO2)

Polished brown-and-cream jasper

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

Tumbled jasper (likely brecciated or common jasper)

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