Mineral (Variety Of Chalcedony)

Polished chalcedony (likely moss or dendritic agate)

Microcrystalline quartz, SiO₂, with iron/manganese oxide inclusions

Polished agate (likely moss or plume agate)

Microcrystalline quartz, SiO₂; chalcedony with brown iron-oxide inclusions

Polished agate (likely carnelian/mossy chalcedony)

Chalcedony, microcrystalline quartz (SiO₂), with iron-oxide banding and possible inclusions

Chalcedony with Quartz

Silicon Dioxide (SiO2)

Carnelian (red-orange chalcedony)

Chalcedony, cryptocrystalline SiO₂; quartz-group mineral

Polished carnelian (likely brecciated agate) heart

Microcrystalline quartz, SiO₂; chalcedony with iron-oxide coloration

Tumbled jasper (likely iron-stained chalcedony)

Microcrystalline quartz, SiO₂; jasper is an opaque variety of chalcedony

Tumbled chalcedony (likely moss or plume variety)

Microcrystalline quartz, SiO₂

Agate (Chalcedony)

Silicon Dioxide (SiO2)

Dendritic agate or included chalcedony (likely tumbled)

Microcrystalline quartz, SiO₂; inclusions likely manganese-oxide dendrites or iron minerals

Jasper

Chalcedony (SiO2)

Jasper

Jasper (Silicon Dioxide, SiO2)

Polished reddish-brown gemstone, likely carnelian

Carnelian: chalcedony, microcrystalline quartz (SiO₂), colored mainly by iron oxides

Chrysoprase

Chalcedony (cryptocrystalline silica containing nickel); Chemical Formula: SiO2 with Ni impurities

Red jasper

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

Polished ocean jasper (orbicular jasper), likely a small tumbled stone

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

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Tumbled banded agate beads

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

Polished picture jasper (likely)

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

Polished agate (chalcedony nodule)

Microcrystalline quartz, SiO₂; agate is banded chalcedony, with possible iron-oxide inclusions

Polished jasper (likely brecciated or red jasper)

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide pigments and possible breccia fragments

Red jasper (likely iron-rich chert)

Microcrystalline quartz, SiO₂, colored mainly by hematite/goethite

Red jasper (probable)

Microcrystalline quartz/chalcedony (SiO₂) colored by iron oxides

Tumbled jasper or iron-rich chert

Microcrystalline quartz (SiO₂), likely colored by iron oxides

Polished brecciated jasper (likely septarian or iron-rich jasper)

Microcrystalline quartz (chalcedony), SiO₂, with iron oxides and possibly calcite or other rock fragments

Jasper

Silicon dioxide (SiO2)

Gray chalcedony (rough, possibly agate-grade)

Chalcedony, microcrystalline quartz (SiO₂)

Blue Chalcedony

Cryptocrystalline Quartz (SiO2)

Polished red jasper

Jasper, an opaque, microcrystalline variety of quartz (SiO₂)

Green chalcedony (likely dyed or treated)

Chalcedony, microcrystalline quartz (SiO₂)

Tumbled agate or chalcedony

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

Chalcedony

Silicon dioxide, SiO2

Polished brown agate (likely)

Microcrystalline quartz, SiO₂ (chalcedony; agate variety)

Likely polished flower agate

Flower agate, a variety of chalcedony (microcrystalline SiO₂)

Tumbled blue chalcedony (possibly blue agate)

Microcrystalline quartz, SiO₂; chalcedony variety

Flower Agate

Silicon Dioxide (SiO2) with Chalcedony inclusions

Tumbled chalcedony or quartz-rich chert

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

Iron-stained chalcedony or jasper

Microcrystalline quartz (SiO₂), likely ferruginous jasper/chalcedony

Agate

Silicon Dioxide (Chalcedony), SiO2

Tumbled carnelian agate

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

Yellow Chalcedony

Cryptocrystalline Quartz (SiO2)

Polished jasper pebble

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