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

Red jasper

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

Blue Agate (Dyed)

Silicon Dioxide (SiO2) - Variety of Chalcedony

Yellow Jasper

Silicon dioxide (SiO2)

Chert (Jasper influence)

Microcrystalline Quartz (SiO2)

Red jasper-like chalcedony pebble

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

Tumbled carnelian (red chalcedony)

Carnelian, a microcrystalline variety of quartz (SiO₂)

Tumbled brown jasper (likely common jasper or chert)

Microcrystalline quartz, SiO₂, chiefly chalcedony/quartz with iron-oxide impurities

Tumbled reddish-brown stone, likely jasper

Jasper (microcrystalline quartz, SiO₂), possibly red jasper or jasper-rich chert

Dyed Blue Agate Slice

Silicon Dioxide (Chalcedony variety), $SiO_2$

Polished jasper pebble

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

Dragon Blood Jasper

SiO2

Tumbled jasper pebble

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

Polished leopard-skin jasper

Jasper (microcrystalline quartz, SiO₂), commonly orbicular or brecciated varieties

Tumbled jasper

Microcrystalline quartz (SiO₂), commonly iron-oxide-bearing chalcedony

Blue Chalcedony

Silicon Dioxide (SiO2)

Quartz (Microcrystalline variety)

Silicon Dioxide (SiO2)

Brown botryoidal chalcedony (likely iron-stained agate)

Microcrystalline quartz, SiO₂; chalcedony/agate variety

Tumbled jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide inclusions

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with impurities of Hematite or Goethite

Tumbled yellowish quartz or chalcedony

Quartz/chalcedony, SiO₂

Jasper (specifically Yellow or Picture Jasper)

Silicon Dioxide (SiO2) with iron oxide inclusions

Polished ocean jasper / orbicular jasper (likely)

Microcrystalline quartz (chalcedony), commonly with iron-oxide and other mineral inclusions

Polished agate (likely)

Banded chalcedony, a microcrystalline variety of quartz (SiO₂)

Quartz (Milky/Chalcedony variety)

Silicon Dioxide (SiO2)

K2 Jasper (K2 Granite)

Azurite in Granite (Biotite Granite with Azurite inclusions)

Banded Agate (Dyed Purple)

Agate (Variety of Chalcedony/Quartz), SiO2

Chalcedony Pebble

Cryptocrystalline Quartz (SiO2)

Agate (Polished Cabochon Slice)

Silicon Dioxide (SiO2)

Honey/brown agate (chalcedony)

Microcrystalline quartz, SiO₂; likely translucent agate or chalcedony

Chalcedony (Quartz variety)

Silicon Dioxide (SiO2)

Tumbled quartz-rich chalcedony (likely carnelian or orange jasper)

Microcrystalline quartz, SiO₂, colored mainly by iron oxides

Tumbled brown jasper (likely)

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

Tumbled Chalcedony

Quartz (Silicon Dioxide - SiO2)

Agate

Chalcedony (Cryptocrystalline variety of Quartz, SiO2)

Polished red-and-cream jasper

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

Red-orange jasper pebble

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

Polished red jasper (likely brecciated or opaque chalcedony)

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

Tumbled jasper pebble

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

Polished jasper or iron-stained chert

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

Blue chalcedony cabochon (likely dyed)

Microcrystalline quartz, SiO₂ (chalcedony)

Polished yellow-orange stone pendant, possibly carnelian or yellow chalcedony

Chalcedony, microcrystalline quartz (SiO₂); identification from the photo is uncertain

Gray Agate

Cryptocrystalline Quartz (SiO2)